After months of delay, Congress’s passage of a nearly $61 billion U.S. aid bill to Ukraine has provided a vital lifeline to Kyiv. But the aid package alone will not solve Ukraine’s larger problems in its war with Russia. Ukrainian forces are defending frontlines that span some 600 miles of the south and east of the country, and prolonged inaction in Washington has left them severely stretched. The influx of U.S. weapons and ammunition should significantly raise the cost to Russia of its impending summer offensive. The aid also offers Ukrainian forces enough materiel to support more systematic military planning for the summer and fall.

Yet ending the war on terms favorable to Ukraine will require far more than a new pipeline of equipment. More than two years since Russia’s full-scale invasion of Ukraine, its objective in the war remains unchanged: the Kremlin seeks to subjugate Kyiv. Inconstant support and political delays among Ukraine’s international partners have left that outcome all too plausible. If Ukraine is to prevent Russian victory in the longer term, it will need a comprehensive strategy. This means training, equipping, and mobilizing new forces. It means convincing the Kremlin that continuing the war will become increasingly risky to Russia over time. And it means establishing a position of sufficient strength to be able to set forth, on Ukraine’s own terms, the parameters of a lasting peace.

None of these tasks will be straightforward, and none can happen overnight. Nor can Ukraine and its international partners afford to fritter away months formulating a way forward. The United States and its NATO allies will need to make explicit long-term commitments; compelling Russia to negotiate will be especially difficult. But the alternatives are far worse. In the absence of such an overall strategy, the duration of the conflict may be extended, but its trajectory will not.

GRIMACING AT GLIDE BOMBS

Since the fall of 2023, Ukraine’s battlefield situation has steadily worsened. Largely because of ammunition shortages, Ukrainian forces have had to cede territory to Russian forces, often after sustaining significant casualties. Russia has amassed approximately 470,000 troops in Ukraine and seems intent on using them to try to complete the conquest of Donbas over the remainder of 2024. Russian forces have been focusing their attacks on key eastern towns that, once taken, will allow them to threaten Ukraine’s main logistics hubs in and around the Donetsk region.

Talk of a new Russian offensive may conjure up images of tank units assaulting Ukrainian lines, breaking through, and then trying to exploit those gains deep into Ukrainian-held territory in order to cut off Ukrainian units. But Russia’s forces are not currently able to carry out these kinds of operations, nor do they intend to. After more than two years of war, Russia’s army has suffered heavy losses among its officer core, and its ability to plan and synchronize large-scale attacks is limited. Russian attacks mainly consist of successive assaults at platoon and company scale, resulting in slow advances with heavy losses.

Ukrainian soldiers manning an artillery position near Chasiv Yar, Ukraine, April 2024
Ukrainian soldiers manning an artillery position near Chasiv Yar, Ukraine, April 2024
Thomas Peter / Reuters

Still, Russia currently enjoys a more than ten-to-one advantage over Ukraine in available artillery. With the passage of the new U.S. aid package, that advantage will likely shrink to three to one in some regions, which will increase the rate of Russian casualties. But Russia has several ways of pulling Ukrainian forces into fights that are also costly to Ukraine. For example, Russian forces have been using converted glide bombs to devastating effect. These are Soviet-designed FAB-500s—large half-ton bombs—that have been outfitted with wings and guidance kits and that are lobbed by Russian aircraft from behind the Russian lines. With an approximately 40-mile range, they can easily strike Ukrainian towns, collapsing buildings and driving out local populations.

As a result, Ukrainian forces have often been forced to expend significant resources defending costly single positions, simply to shield civilian settlements from coming into Russian glide-bomb range. Take Chasiv Yar, a small town on a key ridge line in the eastern Donetsk region. If it falls, Russian forces will gain a commanding position from which to bombard towns in Donbas and key Ukrainian supply routes. Thus, Ukrainian forces are desperately trying to hold on to it, even as the tactical situation becomes less favorable. The challenge has been amplified by Ukraine’s overstretched air defenses, a situation that now permits Russian planes to come close to the frontlines, increasing the accuracy of their bombing. Unfortunately, the more Ukraine needs its surface-to-air missile systems to protect its cities, the greater it puts at risk its ground forces at the front.

Ukraine will lose ground to Russia this summer. The question is how much.

The solution to this challenge would usually be what military strategists call an “active defense,” using small-scale counterattacks to disrupt the attacker’s efforts to consolidate its advances. If, say, Russian forces seized a key position in Chasiv Yar, the Ukrainians could use counterattacks to isolate the position so that the Russians were unable to dig in and keep moving forward. But Ukraine has few reserves and has lost many of the tactical vehicles needed to exploit Russian vulnerabilities soon after they take positions. Lacking the reserves to counterattack, Ukraine must settle for maximizing Russia’s losses for each position it takes, thereby slowing down its rate of advance.

Under these conditions, even the passage of the U.S. aid bill can do only so much to change the battlefield calculus. The long delay in Washington means that it will take time to repair much of the damage to Ukrainian capabilities. Ukraine will lose ground to Russia this summer. The question is how much, and how high a price Ukrainian forces can make the Russians pay for their gains.

FRESH BLOOD, NOT MORE BLOOD

Other than the immediate provision of ammunition, the greatest effect of the new U.S. aid package is the certainty it offers. After months in which the timing and amount of U.S. support was in doubt, Ukraine will now have enough clarity about military resources for the next six months to allow for broader strategic planning.

Paramount is the need to generate new forces. To do so, Ukraine will need to mobilize more people, improve its training pipeline to maintain a qualitative advantage over Russian units, and adequately equip those new troops. Until now this has been impossible. Lacking equipment and weapons, and unable to predict if and when more might arrive, Ukraine’s military leadership was forced to prioritize all materiel for troops already at the front. The size of the U.S. aid package—and the further support of European partners—means that Ukraine’s military leadership can now implement a deliberate plan to train and equip more troops. Contrary to widespread assumptions, Ukraine does not lack people to mobilize. (According to one recent analysis, there could be several million additional Ukrainians who are able to serve.) What it has lacked is an effective recruitment and training system to bring available people into the force and equipment to provision them. These problems can and must be resolved.

Ukrainian commanders must form new brigades rather than simply bringing their existing formations back up to strength. The army currently lacks enough brigades to rotate them as a whole off the frontline. Instead, individual brigades have been rotating exhausted battalions just off the line of contact for brief respites—a strategy that provides rest but does not allow for collective training of the brigade, since brigade staff and enabling equipment remain at the front. Thus, it is crucial for Ukraine to build and train additional brigades now, so that it can mount an active defense in the fall. Over time, these new units will greatly enhance its ability to counterattack.

A member of a Ukrainian artillery brigade in Donetsk region, Ukraine, April 2024
A member of a Ukrainian artillery brigade in Donetsk region, Ukraine, April 2024
Serhii Nuzhnenko / Radio Free Europe / Reuters

The military must therefore pursue mobilization in three stages. First, it must immediately raise battlefield replacements for the existing force. But then it must regenerate reserves to allow existing units to rotate and, after that, build new units able to conduct offensive action. The first is the easiest to solve. Equipment is the limiting factor for the second. For the third, the most limiting factor is officer training. This can be addressed, but it must be done imminently if Ukraine is to generate the needed forces by fall.

Russia will likely be most dangerous in the final months of 2024. By that point, having weathered months of Russian offensive operations, Ukrainian forces will be stretched thin, their air defenses depleted. Russia will likely have enough troops to rotate its units to allow for successive offensives in the fall.

But Russian capabilities are not unlimited. Moscow has made some industrial and military choices that are likely to restrict its offensive potential over the course of 2025. For one, it has decided not to expand production of artillery barrels, with the result that fewer new guns will be available next year. Based on the current loss rate, Russian stockpiles of armored vehicles will also likely be depleted by the second half of 2025. This means that Russian forces will be entirely dependent on newly produced equipment rather than refurbished equipment from existing stock, severely constraining their ability to replenish weapons systems lost in battle. At the same time, beginning in late 2024, European armaments production will begin to climb steadily as investments made last year and in the first months of this year begin to bear fruit. By 2025, then, supply problems should be less acute for Ukraine and more acute for Russia—if Ukraine can hold on until then.

With this longer-term perspective in view, the challenge facing Ukraine and its allies becomes clear. The top priorities must be to ensure not only that Russia’s summer offensive culminates at a high cost to Moscow but also that newly raised Ukrainian troops are in place to blunt further offensives in the autumn—and, ideally, to establish a stable frontline by early 2025. It is only from such a position that Ukraine can regain the initiative. Achieving that objective will depend to a significant degree on how rapidly Ukraine can mobilize and equip its forces. The one commodity it desperately lacks is time.

BRINGING MOSCOW TO THE TABLE

Even if Ukraine is able to blunt Russian gains by rapidly training, equipping, and deploying new forces, these steps will not in themselves produce a pathway to ending the conflict. Ultimately, this is because Kyiv’s international partners have built their case for support on the simpler objective of preserving Ukraine in the fight rather than on compelling Russia to negotiate on favorable terms.

The United States and its European allies need to recognize that helping Ukraine negate Russian attacks is not the same as putting Ukraine in a strong negotiating position. The Kremlin is keen for negotiations based on the war’s current dynamics: it believes that once talks are underway, Ukraine’s Western backers will agree to nearly anything, seeing any settlement that can be reached as successful, even if it fails to protect Ukraine in the long term. And Russia’s demand would remain what it has been throughout: a surrender in all but name. For Moscow to truly negotiate, it must be confronted with a situation in which extending the conflict further will present an unacceptable threat to itself. It is only then that Ukraine will be able to extract meaningful concessions.

Sanctions are only one of the tools for damaging Russia’s financial liquidity.

Russia already faces several pressure points. First, Russia’s battlefield losses of critical systems—such as air defenses—matter, because they form the bulwark of Russia’s conventional deterrence of NATO. Equipping Ukraine to be able to damage or destroy prestige Russian assets is strongly in NATO’s interest. Second, Russia will be unable to fund the war indefinitely. Western sanctions are only one of the tools for damaging the regime’s financial liquidity, and they are less effective than other options. Damage to Russia’s oil infrastructure is likely to have a much greater impact. Although there are good reasons for the West to avoid directly aiding such attacks, that does not mean that Ukraine shouldn’t undertake them.

Third, although the Russian public largely supports the war, there are deep frustrations with the Russian government that can be exploited. So far, Western governments have not aggressively pursued information operations against the Russian government, partly because they are perceived as escalatory and partly because they are not expected to have immediate effect. By contrast, Russia has been conducting active information operations across Europe with the intent of destabilizing the West.

This asymmetry needs to be remedied. Western concerns that information warfare could provoke escalation are unconvincing: the Kremlin is as determined as the White House to avoid a direct confrontation over Ukraine. Moreover, the Kremlin has long assumed that the West has pursued extensive information operations against it since 2011, even though this is not the case. Any potential escalation risk of such operations is therefore already baked in. Moreover, most of the Kremlin’s routes to escalation do not actually involve countering such activities. Given this situation, there is much more that the West can do. Over the longer term, more and better information operations could heighten Moscow’s awareness of the domestic risks that its costly war has stirred up.

THE FIREPOWER FIX

Given the extent to which it is currently outgunned, Ukraine doesn’t yet have the ability to set forth favorable negotiating terms to end the war. A cease-fire would likely see Russia reconstitute its military power, while Ukraine would not be able to maintain its own forces at their current size. Moreover, Kyiv would likely receive waning support for reconstruction if renewed Russian hostilities were anticipated in the near future. Rebuilding Ukraine will depend critically on investment from the private sector, and the threat of a new conflict will make any such financing risky. To ensure that Ukraine can negotiate in the confidence that it can secure a lasting peace, Kyiv’s international partners will have to offer security guarantees that it trusts. Because Ukraine cannot propose those guarantees, it will be up to its international partners to make the first move.

Ultimately, any successful end to the war will depend on NATO’s ability to convincingly deter Russia. That posture requires the alliance not only to field sufficient forces to counter a threat from Russia but also to establish sufficient production capacity among its members to sustain a steady flow of munitions in the event of another war. Establishing this supply will be necessary regardless of how the war ends. In the short term, expanded production of munitions will be essential to Ukraine’s ability to degrade the Russian military. If Ukraine manages to protract the conflict and the war is terminated in its favor, its partners will need munitions to bolster the credibility of their security guarantees. If, on the other hand, Russia achieves its objectives, then these munitions will be needed to underwrite the future security of NATO.

The U.S. military aid package was passed just in time to stave off a Ukrainian collapse. But to truly shift the direction of the war, it will need to be accompanied by a far more comprehensive strategy to successfully end it. And that must come from Washington, its NATO allies, and Kyiv itself.

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  • JACK WATLING is Senior Research Fellow for Land Warfare at the Royal United Services Institute, a London-based think tank.
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