Advance U.S. Interests by Giving Ukraine the Weapons It Needs Now

Introduction

As Ukraine prepares to launch its much-anticipated spring counteroffensive, some in Washington are casting doubt on what Kyiv can achieve.¹ Ukrainian forces no doubt will face considerable challenges, but their battlefield prospects hinge largely on the level of support they receive from the West. The United States and its allies can and must do more to aid Ukraine. Helping Kyiv defeat Russian President Vladimir Putin’s unprovoked aggression and liberate Ukrainian territory is not only the right thing to do but will enhance U.S. and allied security.

To be sure, the Biden administration and America’s Western allies deserve credit for providing Kyiv with substantial amounts of military aid. This support enabled the Ukrainian military to stay in the fight and eventually retake swathes of territory in the country’s east and south. As Kyiv prepares for its spring counteroffensive, the Western coalition has expanded its assistance to help Ukraine restore its “territorial integrity,” as President Joe Biden declared in January.² Of the over $35 billion in U.S. military aid committed to Ukraine since February 2022, nearly half has come since December. Washington has provided new capabilities, such as Bradley infantry fighting vehicles and Stryker armored personnel carriers, as well as combined-arms training for Ukrainian troops. Allies have also stepped up, providing — after much debate — tanks and other armored vehicles.

Yet Ukraine still faces gaps in key areas. The United States and its allies can resolve at least some of these shortcomings if they muster sufficient political will. This additional aid would not be charity but a prudent investment in U.S. national interests. By exhausting Russian forces, America’s Ukrainian partners are diminishing the most immediate threat to the NATO alliance. Supporting Ukraine also strengthens deterrence of China and other authoritarian powers contemplating military action against their smaller neighbors.

The success or failure of Kyiv’s upcoming counteroffensive will likely determine the future trajectory of the war. If it succeeds, Ukraine will not only liberate additional territory but will likely also attract further Western support. This would put Kyiv in a strong position for future fighting and any eventual peace negotiations. But Vladimir Putin is betting that if the counteroffensive fails, U.S. resolve will falter amid calls to push Kyiv into premature peace talks.

Instead, by maximizing support for Ukraine now, the West can help Ukraine shorten the war and make good on the aid already invested. This memo identifies four essential forms of support Kyiv will need for its counteroffensive and beyond. This is not the only assistance Ukraine requires, but it is urgent.

First, the United States and its allies should provide more armored fighting vehicles to fill out the three army corps Kyiv is forming. Ukraine will need these vehicles, along with additional mine-clearing and bridging equipment, to overcome heavily entrenched Russian defenses.

Second, the West needs to address gaps in Ukraine’s air and missile defenses. Otherwise, the Russian Air Force may gain greater latitude both to support Russian ground troops and to strike deep behind the front lines. This could disrupt Ukraine’s counteroffensive.

Third, the Biden administration should grant Kyiv’s longstanding requests for Army Tactical Missile System (ATACMS) missiles. This would allow Ukraine to strike key Russian military targets far beyond the range of its current Western-supplied rocket artillery systems, undermining Russia’s ability to resist attacking Ukrainian forces.

Finally, to help ensure Ukraine has enough artillery ammunition to sustain high-intensity operations, the administration should send Kyiv cluster munitions. While critics note that these munitions can endanger civilians, Ukraine’s elected leaders believe the rewards outweigh the risks. Washington should respect that judgment.

Ukraine stands a good chance of liberating more of its territory in the months ahead. But it needs the tools to do so. While Ukrainians are fighting for their homeland, their efforts contribute directly to the security of NATO and America’s national interests.

Armored Fighting Vehicles

The Ukrainian military will need a large number of armored fighting vehicles (AFVs) during its upcoming counteroffensive, not to mention follow-on phases of the war. The United States and its allies have already pledged a considerable number, comprising a wide variety of infantry fighting vehicles (IFVs), armored personnel carriers (APCs), tanks, and other armored vehicles. IFVs are key for supporting tanks and dismounted infantry, while APCs enable troops to move with greater security, although they generally have limited firepower.

Currently, Kyiv does not have enough armored vehicles. “For our counterattack to be successful, we require an increase in such supplies,” Ukraine’s prime minister explained to Secretary of Defense Lloyd Austin during an April 12 visit to Washington.³ The Ukrainian military will need many AFVs, along with mine-clearing and bridging equipment, to break through Russian lines and then exploit those openings. Without sufficient armored vehicles, Ukrainian troops will likely suffer higher casualties even if their counteroffensive ultimately proves successful.⁴

“For our counterattack to be successful, we require an increase in … supplies” of armored fighting vehicles, Ukraine’s prime minister explained to Secretary of Defense Lloyd Austin during an April 12 visit to Washington.

One can estimate how many AFVs Ukraine needs based on the number of new brigades it is building ahead of the counteroffensive. According to media reports, Kyiv is forming three new army corps, each with six maneuver brigades — or 18 in total — plus support units. The new brigades include several thousand troops apiece, equipped largely using Western aid.⁵ These reports track with open-source evidence confirming that since late last year, Ukraine has sought to stand up or fill out at least that many mechanized infantry brigades and similarly equipped marine and air assault brigades.⁶ Ukraine is also expanding existing units into nine assault brigades under its National Guard⁷ and apparently intends for at least some of them to contain mechanized units.⁸

The typical Ukrainian mechanized infantry brigade includes three mechanized infantry battalions, a tank battalion, and various other sub-units (artillery, engineer-sapper, logistics, etc.). At least on paper, each mechanized infantry battalion should have around 40 IFVs or 45 APCs. The tank battalion should have 40 tanks.⁹

This comes out to at least 120 IFVs/APCs and 40 tanks per brigade. Thus, to fully equip the 18 maneuver brigades Kyiv is forming for its three army corps (not to mention the various other units it is forming), Ukraine would need at least 2,160 IFVs/APCs and 720 tanks. Admittedly, this is a tall order. Perhaps anticipating as much, General Valerii Zaluzhnyi, commander-in-chief of the Ukrainian military, offered a more modest target in December: 600 to 700 IFVs and 300 tanks. (He did not specify a number of APCs.)¹⁰ Units can fight with less than their full complement of armored vehicles, albeit with reduced combat effectiveness.

While the West has pledged a significant number of AFVs, Ukraine is still short. Since October,¹¹ Washington and its allies have promised Kyiv at least 369 IFVs and 603 APCs, including 109 Bradley IFVs and 90 Stryker APCs from the United States. The allies have pledged nearly 420 tanks of various types plus a reported 40 French assault vehicles. As of late April, open-source evidence indicated that at least 199 IFVs and 403 APCs had reached Ukraine, had arrived in Europe for training with Ukrainian troops, or would arrive imminently. For tanks, that number is at least 207 plus at least some of the French assault vehicles.¹² (See the appendix for a detailed breakdown.)

Ukraine’s backers also pledged over 2,000 infantry mobility vehicles (IMVs) since October. But these lack the protection offered by IFVs and APCs like the Bradley and Stryker, while the Bradley also provides superior firepower. The Bradley and Stryker also offer superior communications and situational-awareness systems.¹³

Additional donations are in the works, but many will not arrive for months or longer. Washington plans to deliver 31 refurbished Abrams tanks in the fall.¹⁴ On April 20, Denmark and the Netherlands announced that they plan to procure 14 Leopard 2 tanks from a third party and deliver them to Ukraine in the first quarter of 2024, following refurbishment.¹⁵ Denmark, the Netherlands, and Germany also intend to give Kyiv as many as 178 Leopard 1 tanks.¹⁶ But just 25 will be available by the summer, with another 55 ready by year’s end and another 20-plus in 2024, the German defense ministry said in late March.¹⁷ Finally, the Czech Republic is refurbishing 90 T-72 tanks for Ukraine, financed by the United States and the Netherlands. So far, 37 have reached Ukraine, a Czech official said last month.¹⁸

Sweden pledged around 50 IFVs in January but has given no word on the timeline.¹⁹ Norwegian media reported the country’s military is analyzing whether it can afford to donate its own IFVs to Ukraine.²⁰ Greece has given Kyiv 20 Soviet-made IFVs and plans to send another 20, backfilled by German-made Marder IFVs. But when Germany found itself without enough combat-ready IFVs to fulfill its own commitment to Kyiv, Athens paused its deliveries.²¹ However, in early April, Greece’s defense minister said Athens was ready to dispatch “another shipment.”²²

Kyiv can eventually use these vehicles to replace losses suffered during its counteroffensive, helping ensure it is not left vulnerable to a Russian counterpunch. At the same time, receiving new platforms will add to Ukraine’s logistics and sustainment burden,²³ and securing sufficient ammunition for the Leopard 1’s main gun, which uses a different caliber than that on the Leopard 2, may prove difficult.²⁴ The Leopard 1 also has thin armor, although tank-on-tank fights have been rare in the Russia-Ukraine war, and the Leopard 1 can still be useful as an infantry-support vehicle. Kyiv will need to weigh these issues against the need for additional capacity in its war of attrition with Russia.

But for its counteroffensive to succeed in the first place, Ukraine also needs more tanks and armored vehicles now. The United States and its allies can fill that gap by sending vehicles from their existing stocks to minimize delivery timelines. While some may not arrive until weeks after Kyiv launches its counteroffensive, they will still be useful. The Ukrainian military will face well-entrenched Russian forces and will likely need a steady supply of fresh units to replace losses and maintain momentum. Washington and its allies should aim to consolidate deliveries around as few different models as possible to minimize Ukraine’s logistical and sustainment burden.

Prioritize IFVs and APCs

Although tanks receive a lot of press, donations of Western-made IFVs and APCs, such as the Bradley and Stryker, should take top priority. These vehicles outclass the legacy Soviet-made IFVs and APCs standard within Ukraine’s mechanized infantry units. As analyst Rob Lee has noted, this improvement is generally greater than the difference between Ukraine’s Soviet-era tanks and the Leopard 2.²⁵

Ukrainian troops face a shortage of IFVs and are clamoring for more.²⁶ Many nominally mechanized Ukrainian infantry battalions, including in newly formed brigades,²⁷ rely at least in part on IMVs in place of scarce IFVs and APCs.²⁸ Supplying additional Western IFVs and APCs would provide these units with better protection and firepower. It would also allow Kyiv to reserve more of its Western-supplied IMVs for highly mobile units (reconnaissance, special operations, anti-tank, etc.) currently equipped with civilian vehicles.²⁹

The United States should aim to provide enough Bradley IFVs and Stryker APCs for an additional two brigades. According to The Military Balance 2023, the U.S. Army has around 2,400 M2A2/A3 Bradleys left plus another 2,000 older-model Bradleys in storage. The Army also has around 1,250 M1126 Stryker Infantry Carrier Vehicles left as well as over 400 of the M1256A1 variant.³⁰ Meanwhile, Germany should sprint to refurbish as many Marder IFVs as possible, although these vehicles likely will not arrive until after the counteroffensive.³¹

Among Tanks, Prioritize the Leopard 2

The German-made Leopard 2 is relatively easy to operate, supply, and maintain and has active production lines for ammunition and spare parts. Collectively, NATO allies possess over 2,000 Leopard 2 tanks, making it the best option for Ukraine. Kyiv needs these tanks both to expand its force and because Ukraine is running low on ammunition and spare parts for the Soviet-made tanks it currently uses.³²

Thus far, however, Europe has struggled to deliver. In January, a Ukrainian official said a dozen countries had agreed to supply Kyiv with around 100 Leopard 2s.³³ But some European capitals have discovered they have fewer combat-ready tanks than anticipated, while others are reluctant to see their relatively small fleets depleted.³⁴

To persuade European countries to donate more Leopard 2s to Ukraine, the United States could offer to replace them with Abrams tanks. In particular, Washington could try to redirect Ukraine’s 31 Abrams tanks (expected to arrive in the fall) to a country willing to immediately transfer Leopard 2s to Kyiv. Ukraine would thus get its tanks sooner while avoiding the challenges of supplying and maintaining Abrams tanks.³⁵

In February, a senior NATO official said Finland had indicated it might be willing to send some of its Leopard 2 tanks after completing its accession to NATO, which it now has.³⁶ Helsinki reportedly operates 100 Leopard 2s and has another 100 in storage.³⁷ Greece and Turkey each have over 300 Leopard 2 types but have yet to pledge any to Ukraine.³⁸

In January, German media reported that Berlin would have around 29 Leopard 2s ready for transfer to Slovakia and the Czech Republic by this spring to replace tanks donated to Ukraine. The United States and Germany should encourage Bratislava and Prague to allow Berlin to postpone delivery to redirect these Leopard 2s to Ukraine. Notably, German company Rheinmetall reportedly has another 22 Leopard 2s that can be ready by late 2023 or early 2024.³⁹ They could replace most of the 29 Leopard 2s intended for Slovakia and the Czech Republic.

Finally, Washington should push other Western nations to contribute financing for Czech refurbishment of additional T-72 tanks, which Ukrainian troops already know how to operate. In mid-April, a Czech official said his country could “increase the production rate by dozens more” tanks “if [international] partners are interested in financing this project.”⁴⁰

Air Defense

Ukraine faces a looming air defense crisis. It is running dangerously low on interceptor missiles for Soviet-made air defense systems that have held the Russian Air Force at bay and blunted the impact of Russian missile and drone strikes. If not filled, Ukraine’s air defense gap could grant Russia a major boost on the battlefield, helping it to support ground forces more effectively from the air and enabling strikes deep behind Ukrainian lines. While a medium-term gap may be unavoidable to some degree, the United States and its allies can take steps to mitigate it while working to shore up Ukrainian air defenses over the longer term. In the latest meeting of the Ukraine Defense Contact Group in April, Secretary Austin rightly pledged that Washington would “do everything [it] can to ensure that Ukraine has adequate … ground-based air defense capability.”⁴¹

In the latest meeting of the Ukraine Defense Contact Group in April, Secretary Austin rightly pledged that Washington would “do everything [it] can to ensure that Ukraine has adequate … ground-based air defense capability.”

Because Russia has failed to destroy most of Ukraine’s long-range S-300 (PS, PT, and V1 variants) and medium-range Buk-M1 surface-to-air missile (SAM) systems, Russian fixed-wing aircraft tend to stay outside their range.⁴² When they do venture near the front lines, Russian aircraft typically fly low to avoid Ukraine’s long/medium-range air defenses, yet this renders them vulnerable to Ukrainian man-portable air defense systems (MANPADS), or shoulder-fired SAMs. Russian attack aircraft and helicopters tend to launch unguided rockets at a lofted pitch to increase range and minimize exposure to Ukrainian MANPADS. However, this reduces the effectiveness of Russian close air support for ground troops (although Ukrainian officials say Russian aircraft have recently begun using guided glide bombs from standoff ranges with greater frequency).⁴³ Ukrainian air defenses have also prevented the Russian Air Force from getting close enough to conduct air interdiction missions or strike key Ukrainian logistical infrastructure using unguided bombs.

However, after over a year of high-intensity warfare, Kyiv is running critically low on interceptors for its Soviet-made SAM systems. Moscow’s missile and drone strike campaign targeting Ukrainian critical infrastructure has exacerbated this shortage.⁴⁴ Once Ukraine runs out of these interceptors, which it does not produce, Russian aircraft will have much greater latitude at medium to high altitudes, out of MANPADS range. They will still have to watch out for Kyiv’s Western-donated air defense systems, but much of Ukraine’s airspace will be left undefended. Ukrainian fighter aircraft will continue to patrol but will remain outmatched by Russian advantages in missile range and radar performance.

So far, Russia’s missile and drone campaign has continually damaged Ukraine’s power grid but failed to cripple it. With Ukrainian air defenses heavily degraded, however, Moscow would stand a far better chance. Likewise, Russian aircraft could provide better support to ground troops, bolstering Russian assaults and helping to thwart Ukrainian attacks. Russian aircraft would also have greater latitude to fly deep into Ukrainian airspace to target key logistical nodes such as railheads and bridges that enable equipment and supplies to reach the front.

Granting Kyiv’s requests for a Western fighter such as the F-16, while likely necessary over the medium to long term, would not solve Ukraine’s near-term air defense problem. Retraining Ukrainian pilots on the F-16 would take at least six to 12 months, even on an accelerated timeline.⁴⁵ Training Ukrainian troops to maintain the aircraft will take even longer, meaning Western contractors would need to perform that role in the interim.

Moreover, while the F-16 would grant Kyiv additional capacity to offset attrition among its Soviet-made fighter fleet, the versions of the F-16 Washington would likely be willing to give Ukraine would not provide much additional capability. The United States would likely decline to share anything newer than the Block 30 version and the APG-68 radar, due to concerns that more advanced technologies could fall into Russian (and Chinese) hands. Washington would likely send Kyiv Advanced Medium-Range Air-to-Air Missiles, or AMRAAMs, older than the C5 version. Ukrainian F-16s would remain highly vulnerable to Russian SAMs, in turn preventing them from flying high and fast to exploit the full range of their new air-to-air missiles. Ukrainian fighters would also remain overmatched by advanced Russian aircraft armed with R-77-1 long-range and R-37M very-long-range air-to-air missiles.

Therefore, while Washington and its allies should begin laying the groundwork now to equip Ukraine with Western-made fighters, they will have to look elsewhere to address Kyiv’s near-term air defense requirements. The most immediate task is to replenish Ukraine’s stocks of Soviet-made air defense systems and interceptors. Unfortunately, options here are limited. Slovakia has already donated its sole S-300PMU battery to Ukraine.⁴⁶ Bulgaria and Greece also operate the S-300PMU and S-300PMU1, respectively. But Sofia has flatly refused to transfer its S-300s,⁴⁷ while Greece insists its S-300s must be promptly replaced by U.S.-made Patriots,⁴⁸ which are already in short supply.

Washington could, however, try to persuade Greece by offering to move it higher up on the Patriot delivery queue. Athens could jump Switzerland, which plans to buy five Patriot fire units but has refused to send much-needed Gepard air defense ammunition to Ukraine.⁴⁹ At the very least, the United States could ask that countries unwilling to relinquish entire systems instead donate any spare interceptors that can be fired by Ukraine’s existing systems.

In addition, if they have not already, the United States and its allies should look into helping Ukraine refurbish any old S-300 or Buk-M1 interceptors it has in storage. Meanwhile, Kyiv and its backers should explore how to launch production of these interceptors in a NATO country.⁵⁰ The West should also ensure Ukraine has enough missiles for Buk launchers it has modified or will modify to fire the RIM-7 Sea Sparrow, which is more plentiful.⁵¹

The transatlantic allies should likewise strive to ensure Ukraine has enough missiles for its Western-donated NASAMS medium-range air defense systems, balancing against the need to maintain sufficient U.S. and allied stocks. To get Kyiv more NASAMS launchers, the United States could offer to backfill immediate donations using the six NASAMS batteries Raytheon is currently building for Ukraine.⁵² Washington has (unsuccessfully) made this proposal to Middle Eastern allies but could offer a similar deal to countries such as Spain or Australia.⁵³

Furthermore, the West could expand deliveries of MIM-23 Hawk medium-range SAM systems, building on the handful already delivered or pledged by the United States and Spain.⁵⁴ These systems are outdated, offering limited range and lacking sophisticated guidance. But they would be better than nothing and could at least complicate operations by Russian aircraft. Romania, Greece, Turkey, and soon-to-be NATO member Sweden, along with Japan and Taiwan, all possess MIM-23 variants.⁵⁵

In addition to bolstering Ukraine’s defenses, Washington should attack this problem from the offensive side. Kyiv could degrade Russian air power by targeting airbases housing Russian aircraft operating in and around Ukraine. The Ukrainian military has already conducted several successful strikes against Russian airbases, apparently using one-way attack drones.⁵⁶ But to conduct an effective strike campaign targeting Russian airbases, Ukraine will need enhanced long-range precision-strike capabilities.

This should include the ATACMS, as discussed in the next section. But as FDD’s Ryan Brobst has argued, the West could also help Ukraine build inexpensive long-range one-way attack drones akin to the Iranian-made Shahed-136/131.⁵⁷ Various Ukrainian organizations are already developing drones along these lines but lack the ability to produce them en masse.⁵⁸ That is where a Western company could step in.

ATACMS

The Army Tactical Missile System, or ATACMS, would enable Ukraine to strike high-value Russian military targets, such as key logistics nodes, command posts, and air bases, far beyond the range of its current rocket artillery. Even a small number of these missiles could help Ukrainian forces degrade Russia’s ability to resist their advances. Kyiv has been asking for ATACMS for about a year now, but the Biden administration continues to refuse. The administration’s arguments against giving Ukraine ATACMS are shaky. Moreover, by denying Kyiv this key capability, Washington makes the war more likely to remain a protracted war of attrition, which could play to Moscow’s advantages over time.

ATACMS is a short-range ballistic missile that can be fired from the M142 High Mobility Artillery Rocket System (HIMARS) and from the M270 Multiple Launch Rocket System (MLRS). Ukraine already operates HIMARS and MLRS, provided by the United States and United Kingdom, respectively,⁵⁹ as well as German and French variants of MLRS,⁶⁰ although the United States modified the donated HIMARS so they cannot fire ATACMS.⁶¹ Modern ATACMS variants have a range of up to 300 kilometers (186 miles) and carry a 500-pound unitary warhead.⁶² This means they can hit targets at roughly three to four times the range of the munitions currently fired by Ukraine’s Western-supplied rocket artillery, with a warhead approximately 2.5 times bigger.⁶³

Ukrainian forces could use ATACMS to strike logistics nodes, command-and-control posts, and other high-value targets deep behind the front lines. For example, Russia’s logistics hubs in the occupied cities of Luhansk and Dhzankoi lie beyond the range of Ukraine’s current Western-supplied rockets but would make easy targets for ATACMS. The Ukrainian military could also strike Russian air defense systems as well as airbases from which Russian aircraft conduct combat air patrols or provide close air support for ground forces. Perhaps most important, Ukraine could strike the Kerch Bridge, the main supply route for Russian forces in southern Ukraine.

As General Christopher Cavoli, the top U.S. commander in Europe, reportedly explained to lawmakers in February, these longer-range missiles would facilitate Ukraine’s counteroffensive.⁶⁴ An ATACMS strike campaign would undermine not only Russia’s offensive potential but also its ability to resist attacking Ukrainian forces.⁶⁵ Indeed, Ukraine’s previous counteroffensives in the country’s east and south succeeded in part due to HIMARS/MLRS strikes targeting Russian logistics and command and control. However, the Russians have adapted, including by moving their supply depots and command-and-control posts beyond the range of Ukraine’s current Western supplied rocket artillery.⁶⁶ Ukraine thus needs a longer-range system to achieve similar disruptive effects.

Giving Ukraine ATACMS would facilitate its upcoming counteroffensive, according to General Christopher Cavoli, head of U.S. European Command and Supreme Allied Commander Europe.

By softening up Russian defenses, ATACMS could also help Ukraine shift toward an emphasis on maneuver rather than the artillery-centric attritional warfare that has largely dominated the conflict thus far. Washington hopes that Ukrainian forces can utilize Western-donated armor and U.S.-provided combined-arms training to fight more like the United States, relying on maneuver to take territory rather than massive amounts of artillery fire.⁶⁷ This could reduce Ukraine’s expenditure of artillery ammunition, making the fight more sustainable as Western stockpiles dwindle.⁶⁸ Although Moscow has been forced to conserve artillery shells,⁶⁹ it retains a quantitative advantage in artillery fires and is racing to ramp up artillery shell production.⁷⁰

To date, however, Ukrainian forces have executed successful maneuver operations only where Russia’s defenses were weak. But Kyiv will likely have no such luxury in the months ahead. The Russians have built fortified defensive lines across the battlefield and have heavily mined potential Ukrainian avenues of advance.⁷¹ According to Ukraine’s military intelligence chief, mobilization has roughly doubled the number of Russian soldiers in Ukraine,⁷² who have a shorter front line to defend following Russia’s retreats last fall. Moscow no longer suffers the crippling shortage of manpower that facilitated Ukraine’s stunning counteroffensive in Kharkiv Oblast last September.⁷³

The Biden administration is belatedly moving to provide Kyiv with a different long-range precision-strike system, but it will not be ready for many months and has just half the range of ATACMS. In February, following months of deliberation, the Biden administration decided to send Ukraine the Ground Launched Small Diameter Bomb.⁷⁴ That system, which has a range of roughly 150 kilometers, could strike some of the same targets as ATACMS, although it has a much smaller warhead. But it will not arrive in Ukraine until the fall,⁷⁵ and fielding the system in substantial numbers will take even longer. ATACMS therefore remains the best option.

Despite the clear military rationale, the White House continues to refuse Kyiv’s pleas for ATACMS. The administration has offered two justifications. First, since last spring, the administration has argued that providing Ukraine with the capability to strike nearly 200 miles inside Russian territory could lead Moscow to escalate.⁷⁶ The fear is that Russia could retaliate conventionally against NATO or use a tactical nuclear weapon against Ukraine.

Regarding the former, Putin appears keen to avoid a direct conflict with the United States and NATO, particularly when the bulk of Russia’s military is tied up — and badly degraded — in Ukraine. Indeed, even as Washington and its allies have plied Kyiv with weapons, Moscow has responded with plenty of hostile rhetoric but no tangible steps that indicate any readiness for a wider conflict.⁷⁷

Russian nuclear escalation against Ukraine, such as a demonstrative use or battlefield employment of a tactical nuclear weapon, is more plausible, yet precedent suggests an ATACMS strike alone would not be a probable trigger. Despite his nuclear saber-rattling, Putin refrained from nuclear use even after Ukraine conducted numerous strikes in Crimea and within Russia proper.⁷⁸ Nor did Putin employ nuclear weapons when Ukraine embarrassed Moscow by retaking swathes of territory in Kharkiv and Kherson oblasts. The Biden administration itself has reportedly recognized that strikes against Russian targets in Crimea likely would not trigger Putin’s nuclear threshold.⁷⁹ A strategic collapse of Russian forces on the battlefield might lead Putin to consider extreme measures, yet ATACMS strikes alone would not have that kind of strategic impact.

Moreover, Washington could mitigate the risk of escalation by conditioning the provision of ATACMS on a Ukrainian commitment to use the missiles only against targets in occupied Ukrainian territory. This includes the Donbas and Crimea, which the United States and almost every other country recognize as sovereign Ukrainian territory. Kyiv has honored a similar commitment pertaining to its current Western-provided rocket artillery.⁸⁰ While this restriction hardly seems fair given that Russia continues to strike civilian targets across Ukraine, it would strike a balance between the twin goals of helping Kyiv defeat Kremlin aggression and avoiding escalation.⁸¹

The administration’s second reason for not sending ATACMS is its claim that the United States simply lacks enough of these missiles to spare. Foreign Policy reported in December that Pentagon officials had argued as much to deflect congressional pressure to provide ATACMS. In February, Politico reported that Pentagon officials had delivered this message directly to their Ukrainian counterparts.⁸² General Mark Milley, chairman of the Joint Chiefs of Staff, said something similar in late March.⁸³

This argument seems dubious. Lockheed Martin has reportedly produced over 4,000 ATACMS of various types for the U.S. military and its allies. Although the United States has launched roughly 600 in combat,⁸⁴ thousands remain in U.S. and allied stockpiles. The National Defense Authorization Act for Fiscal Year 2023 authorized the Pentagon to engage in a multi-year contract to buy 1,700 ATACMS, which can backfill any missiles sent to Ukraine. Since Russia launched its 2022 invasion, the Pentagon’s Defense Security Cooperation Agency has greenlit Australia,⁸⁵ Estonia,⁸⁶ Lithuania,⁸⁷ Poland,⁸⁸ the Netherlands,⁸⁹ and Morocco⁹⁰ to buy a total of 211 ATACMS. What is more, the U.S. military is already planning to replace ATACMS with the more capable Precision Strike Missile, expected to reach initial operating capability this year.⁹¹

The Ukrainian military could achieve significant military effects with even a small number of ATACMS. Congress would be wise to press the Pentagon to prove it cannot afford to send Kyiv even a few dozen of these missiles.

Washington has invested billions of taxpayer dollars in helping Ukraine claw back its territory. More important, the United States has a vital interest in defeating Russia’s aggression. It would be foolish to deny Kyiv a key capability that can help it make good on America’s investment.

Artillery Ammunition

The Ukrainian military, like its Russian adversary, relies heavily on artillery. However, Ukraine faces a shortage of artillery ammunition. In March, Ukrainian President Volodymyr Zelenskyy said artillery rounds, along with the systems to shoot them, are the “number one” thing his military needs.⁹² Washington can take two steps to help fill that gap. First, the Biden administration should provide Ukraine with cluster munitions, specifically the Dual-Purpose Improved Conventional Munition (DPICM). Second, the Pentagon should reevaluate U.S. requirements for a potential war with Russia, thereby freeing up additional U.S. aid for Kyiv.

Prior to Moscow’s 2022 invasion, Russia destroyed a significant portion of Ukraine’s artillery ammunition stocks in covert operations,⁹³ even sabotaging Eastern European suppliers of ammunition to Ukraine.⁹⁴ Russian operatives also bought up ammunition from private sellers to prevent it from going to Kyiv. That effort continued following the full-scale invasion, along with strikes against Ukrainian ammunition depots and defense factories.⁹⁵

Ukraine was already running low on Soviet-standard 152mm and 122mm artillery shells by last summer.⁹⁶ Its stocks of those shells are now nearly exhausted. Washington and its allies have scoured the Earth for additional sources of Soviet-standard ammunition,⁹⁷ and some factories in Eastern Europe have resumed or boosted production.⁹⁸ Ukraine, in cooperation with NATO partners, has even established limited production of 152mm and 122mm artillery shells,⁹⁹ although their quality is questionable. Still, demand far outstrips supply, leaving Ukraine overwhelmingly reliant on Western supplies of NATO-standard artillery ammunition, primarily 155mm shells.

But Washington and its allies are struggling to meet Kyiv’s needs. In March, Defense Minister Oleksiy Reznikov said Ukraine expends around 110,000 155mm shells a month, or roughly 3,700 per day. If they “were not limited by the amount of available artillery shells,” Ukrainian forces could fire more than five times as many shells, Reznikov stated. Although Moscow has also had to conserve shells as the war has dragged on, Reznikov said Russia still fires several times more than Ukraine.¹⁰⁰

Washington has already sent or promised Ukraine over 1.5 million 155mm artillery shells and more than 450,000 105mm rounds.¹⁰¹ But U.S. stocks are dwindling.¹⁰² The same goes for European countries, many of which began the war with paltry stockpiles of artillery ammunition.¹⁰³ In mid-March, an EU official told Politico that the bloc had thus far sent Ukraine a total of 350,000 155mm artillery shells.¹⁰⁴

As NATO Secretary-General Jens Stoltenberg noted in February, Ukraine expends artillery shells “many times” faster than the West can make them.¹⁰⁵ The United States and Europe, like Russia, are working to increase production. But it will take time. In January, The New York Times reported that the Pentagon aimed to increase U.S. monthly production of unguided 155mm artillery shells from 14,400 to 90,000 by 2025.¹⁰⁶ In late March, however, Army Under Secretary Gabe Camarillo said U.S. monthly production capacity would reach 24,000 by year’s end, hit 75,000 in 2025, and take until 2028 to reach 85,000.¹⁰⁷

Europe, which produces around 20,000 to 25,000 155mm shells per month,¹⁰⁸ faces similar delays. The European Union has agreed to provide Ukraine with 1 million artillery rounds, taking half from existing stocks or pending orders and jointly procuring the rest while also working to increase production capacity.¹⁰⁹ But European governments have been slow to finalize contracts with industry, and officials and industry executives say shortages of key inputs will prevent European firms from ramping up artillery shell production for up to three years.¹¹⁰

Consequently, Kyiv’s “shell hunger” will likely persist and may even worsen over the medium term. This shortage has undermined Ukraine’s efforts to repel Russian advances in places such as Bakhmut.¹¹¹ If not resolved, it could also hamstring Kyiv’s upcoming counteroffensive, which will likely require Ukrainian forces to expend more munitions than when they were playing defense. Kyiv estimates it will need at least 356,400 shells per month — just under 12,000 per day — to achieve its military objectives, according to Reznikov.¹¹²

In March, a senior Pentagon official described recent U.S. artillery ammunition pledges, intended to help shore up Ukraine’s supplies for the counteroffensive, as a “last-ditch effort” due to Western shortages. This suggests deliveries may wane.¹¹³ A reported deal to borrow half a million 155mm shells from South Korea could buy the United States greater flexibility.¹¹⁴ But the fundamental problem remains.

Send DPICM to Ukraine

Washington has a large supply of artillery ammunition that it has yet to tap: DPICMs. Effective against both infantry and armored vehicles, the DPICM is a type of warhead that breaks apart and releases smaller explosive submunitions, or bomblets, increasing lethality. The United States reportedly possesses almost 3 million DPICMs, according to a March 21 letter from the top Republicans on the House and Senate armed services and foreign affairs committees. They noted that “DPICM could help fill a key gap for Ukraine’s military.”¹¹⁵ Many of the DPICM rounds in U.S. stocks can be fired by Kyiv’s Western-donated 155mm or 105mm artillery systems. While some are probably past their shelf life, Ukraine would benefit greatly from even a few hundred thousand.

“DPICM could help fill a key gap for Ukraine’s military,” argue Sens. James Risch (R-ID) and Roger Wicker (R-MS) and Reps. Michael McCaul (R-TX) and Mike Rogers (R-AL).

Kyiv has been asking for DPICMs since last summer.¹¹⁶ But the Biden team has demurred,¹¹⁷ likely fearing criticism from within the Democratic Party and in parts of Europe. Cluster munitions are controversial because some of their submunitions often fail to detonate, leaving behind unexploded ordnance, which can harm unsuspecting civilians or friendly troops. Like the United States, neither Ukraine nor Russia has joined the Convention on Cluster Munitions, which bans parties from using, producing, stockpiling, or transferring these weapons. Poland and Romania, through whose territory Washington would likely deliver the DPICMs to Ukraine, also have not joined.¹¹⁸ Both Russia and Ukraine have already used cluster munitions in the war,¹¹⁹ so giving Kyiv DPICMs would not break new ground from a normative perspective.

As the lawmakers noted in their letter, the U.S. military relied on similar cluster munitions to counter Soviet advantages in manpower, artillery, and armor during the Cold War. The Russian military today enjoys similar numerical advantages against Ukraine, employing some of the same Soviet-era vehicles the DPICM was designed to defeat. These munitions would likely be especially effective against the infantry-heavy assault units Russia has used to advance in Bakhmut and has increasingly employed elsewhere on the battlefield as well.¹²⁰ Sending DPICMs now would also enable Kyiv to conserve more of its traditional artillery shells, which would pose less of a threat to Ukrainian troops advancing across the battlefield during their counteroffensive.¹²¹

Ukraine’s elected representatives understand the dangers that cluster munitions pose. But facing an existential threat from Russia, they believe the rewards outweigh the risks. The many atrocities committed by Moscow’s troops make clear that Kyiv can best protect its citizens by repelling the Russian invaders. Plus, as Ukrainian officials argue, the Ukrainian military would be firing DPICMs in areas that are already largely depopulated and littered with unexploded ordnance.¹²²

Although U.S. law prohibits the transfer of cluster munitions whose submunitions have a “dud” rate exceeding 1 percent,¹²³ the president can use Section 614 of the Foreign Assistance Act to waive that prohibition.¹²⁴ Some DPICM rounds have a dud rate of just over 1 percent, according to Under Secretary of Defense for Policy Colin Kahl, a difference so minor it should not prevent their transfer to Ukraine.¹²⁵

President Biden should respect Kyiv’s decision and send DPICMs now. If he does not, he may be forced to do so later as its ammunition shortage grows more dire, wasting valuable time, battlefield opportunities, and Ukrainian lives.

Update Pentagon Munition Requirements

Since last year, U.S. military and defense officials have pointed to munitions requirements for a potential war with Russia to argue Washington cannot afford to provide certain munitions to Kyiv. Pentagon officials reportedly first offered this justification with respect to ATACMS but later made similar arguments with respect to 155mm artillery ammunition, among other things.¹²⁶ It is time to revisit these requirements.

While the Pentagon should always ensure American warfighters have sufficient ammunition, there are also risks in being overly cautious. Russia’s military has lost an enormous amount of manpower and materiel in Ukraine, including millions of artillery rounds, and will likely need years to return to its pre-war strength. While the Kremlin theoretically could still launch a relatively small-scale invasion against NATO in Eastern Europe, Russia’s military will not pose the same conventional threat for some time. What is more, every Russian tank or artillery piece destroyed by a U.S.-donated shell is one that American or allied forces would not have to face in a potential war with Moscow.

For these reasons, members of Congress have pushed the Pentagon to update its assessment of U.S. munitions requirements for Russia-related contingencies.¹²⁷ In December, The Wall Street Journal reported that the Defense Department planned to review its requirements.¹²⁸ But on March 21, a bipartisan group of lawmakers on the Senate Armed Services Committee asserted that the Pentagon “has not reassessed its European theater warfighting requirements since Russia’s invasion of Ukraine and does not anticipate significantly changing them until FY2026.” The senators called on the Defense Department to “immediately undertake an urgent and comprehensive update to its warfighting requirements for confronting Russia in Europe.”¹²⁹

The Pentagon should “immediately undertake an urgent and comprehensive update to its warfighting requirements for confronting Russia in Europe,” Senators Tom Cotton (R-AR), Richard Blumenthal (D-CT), Roger Wicker (R-MS), and Angus King (I-ME) wrote in a recent letter to Secretary of Defense Lloyd Austin.

In late March, General Milley testified that Secretary Austin had directed the U.S. military to review all its war plans and munitions requirements.¹³⁰ Congress should now press the Pentagon to complete that review in a timely manner.

Conclusion

The United States and its allies have rightly invested considerable resources in helping Ukraine fend off Russia’s invasion and liberate territory. As Kyiv prepares for its counteroffensive in what may prove to be the decisive phase of the war, Washington must do everything it can to help Ukraine make good on that investment. This means supplying Kyiv with more armor, addressing its missile defense gap, bolstering Ukraine’s long-range strike capabilities, and freeing up additional supplies of artillery ammunition.

The Ukrainian people are not asking Americans to fight for them, only for the weapons they need to defend their homes. By heeding that call, Washington advances vital interests both in Europe and beyond. Now is the time to act.

Appendix

Estimated Tally of Western AFVs Provided to Ukraine Since Oct. 2022

Sources: author research and Oryx¹³¹