The Critical Role of U.S. Weapons in Ukraine’s Defense
Ukraine’s ability to withstand the Russian invasion hinges significantly on the supply of American-made weapons. Without billions of dollars in U.S. military aid, Ukrainian forces may soon find themselves overwhelmed. The timeline for when this might happen depends on how quickly Europe and Ukraine can compensate for the artillery, missiles, air-defense systems, and other critical arms that have been put on hold by the Trump administration. The United States had pledged to deliver up to $11 billion in weapons and equipment to Ukraine this year, though a former senior U.S. defense official estimates the actual figure is closer to $9 billion. Much of this aid is either drawn from Pentagon stockpiles or ordered through new defense contracts.
Europe, despite its vocal support for Ukraine, faces significant challenges in filling the gap left by the pause in U.S. aid. European defense industries have ramped up production, but progress has been uneven, and individual countries must also maintain their own military stockpiles. This makes it nearly impossible for Europe to quickly replace the scale and quality of American weapons. Lt. Gen. Ihor Romanenko, a former deputy of Ukraine’s military general staff, has stated that Europe cannot match the level of support provided by the United States.
Meanwhile, Ukraine is doing what it can to bolster its defenses. The country is producing drones and building domestic artillery systems, with plans to allocate 26% of its budget to defense this year. However, Ukrainian officials warn that without continued U.S. support, the military will face severe difficulties. Some analysts believe Ukraine may have only about six months of resilience without systematic American assistance, but even this estimate may be overly optimistic. Mark F. Cancian, a former White House weapons strategist, predicts that Ukrainian forces could begin to buckle within four months due to insufficient munitions and equipment replacements.
Why Europe Can’t Fill the Gap
The scale of U.S. military aid to Ukraine is unparalleled. Out of the $136 billion in military assistance provided to Ukraine since the start of the Russian invasion in February 2022, nearly half came from the United States, according to the Kiel Institute for the World Economy. While European defense production has accelerated, the region still struggles to match the quantity and quality of U.S. arms. Currently, only about 20% of the military hardware supplied to Ukraine comes from the United States, but this 20% includes some of the most critical and advanced systems.
The United States, as the world’s largest economy, has more resources to allocate to defense. For instance, its Air Force has 17 large electronic surveillance aircraft, compared to only three in the UK. The U.S. also contributes over half of NATO’s fighter jets and ground-attack aircraft. In contrast, European defense industries face significant constraints, including limited production capacity, supply chain bottlenecks, and the need for long-term contracts to justify investments in new manufacturing.
European Commission President Ursula von der Leyen has announced an $841 billion plan to increase defense budgets and encourage joint procurement among EU states to speed up weapons production. However, previous efforts have been slow to materialize, as European countries grapple with competing domestic priorities and the high costs of producing advanced weapons. Von der Leyen acknowledged the challenge, emphasizing the need for Europe to act decisively and with urgency.
What Is Ukraine Doing to Arm Itself?
Despite the challenges, Ukraine is taking steps to bolster its defenses. Prime Minister Denys Shmyhal has expressed confidence in Ukraine’s ability to maintain the situation on the front lines, though he has not disclosed details of the country’s remaining stockpiles to avoid revealing vulnerabilities to Russia. Ukraine is producing its own artillery and armored vehicles, with plans to increase domestic production capacity later this year. Last year, the country built over one million drones, and it intends to expand production further in 2025.
Ukraine is also attempting to develop its own air defense systems, including ones as sophisticated as the American-made Patriot system. Each Patriot system, which can intercept ballistic missiles, costs $1 billion and takes up to two years to build. While Ukraine has received seven Patriot systems from the U.S. and Germany, at least two have been destroyed. Other shorter-range air defense systems have been provided by European allies, including the UK, France, and Romania.
However, Ukraine’s vast size and the intensity of Russian bombardment make it impossible to defend every location. “You’re always going to have to pick and choose—you aren’t going to be able to defend against everything,” said Douglas Barrie, a military aerospace expert. This reality underscores the ongoing need for external support to sustain Ukraine’s defenses.
Is Ukraine Doomed Without U.S. Aid?
The suspension of U.S. military aid has raised concerns about Ukraine’s ability to hold out against Russia. In a study titled “Is Ukraine Now Doomed?” Mark F. Cancian warns that without American support, Ukraine may be forced to accept an unfavorable peace agreement with Russia. This could involve ceding up to a fifth of its territory and abandoning its aspirations to join NATO. Some allies may also reduce their own aid, viewing the situation as a “lost cause” without U.S. involvement.
In addition to the pause in weapons deliveries, the Trump administration has also suspended intelligence-sharing with Ukraine, according to CIA Director John Ratcliffe. He suggested that this pause might be lifted if Ukrainian President Volodymyr Zelensky shows more willingness to pursue a cease-fire with Russia as proposed by the Trump administration. Further concerns have been raised about Ukraine’s potential loss of access to Elon Musk’s Starlink satellite internet system, which has been crucial for military communication.
Former Biden administration official David Shimer warns that halting security assistance will weaken Ukraine’s negotiating position with Russia and undermine its ability to achieve a just peace. “The United States should be focused on strengthening, not weakening, Ukraine’s hand ahead of a negotiation,” he said.
Europe’s Efforts to Boost Defense Spending
In response to the urgency of the situation, Ursula von der Leyen announced a sweeping $841 billion plan to increase defense budgets across Europe and encourage joint procurement of weapons. The goal is to accelerate the production of much-needed arms for Ukraine while strengthening European defense capabilities. However, past efforts have faced challenges, as European countries balance domestic spending priorities with the high costs of weapons production.
European defense production has shown some progress, particularly in artillery, where output is now nearly keeping up with wartime demands. This marks a significant shift for an industry that had shrunk after the end of the Cold War. However, the production of more advanced systems, such as air defenses, remains a struggle. Expanding production requires time to hire and train workers, expand factories, and secure rare materials—a process that cannot be rushed without significant upfront investment.
Industry executives emphasize that long-term contracts, often spanning at least a decade, are needed to justify such investments. However, some governments have been reluctant to commit to these agreements. Camille Grand, a former NATO official and current weapons expert at the European Council on Foreign Relations, noted that Europe is not operating on a “war economy footing” and that political will is needed to move defense contracts forward. “Money is not sufficient to solve everything,” he said.
The Broader Implications
The pause in U.S. military aid to Ukraine has significant implications for the broader geopolitical landscape. If Ukraine’s military falters, it could lead to a shift in the balance of power in Europe and embolden Russia in its aggression. The situation also highlights the critical role of the United States in maintaining global security and the challenges Europe faces in stepping up to fill the gap.
As the conflict drags on, the international community is left to grapple with the consequences of reduced U.S. involvement and the limitations of European defense capabilities. The outcome will depend on whether Europe can muster the political will and resources to support Ukraine adequately and whether the United States resumes its role as a primary supplier of military aid. For now, the fate of Ukraine—and the stability of Europe—hangs in the balance.
