Ukrainian Aspirations for U.S. Defense Ties

As Ukraine has become more important to the defense of NATO’s eastern flank, it may aspire to a long-term defense relationship with the U.S. more akin to those with some other key middle powers, such as Poland or South Korea. Like them, Ukraine may seek a U.S. relationship beyond training and the supply of arms. 

Since Russia’s full-scale invasion in 2022, Ukraine’s value to U.S. security has risen. If Russia were to defeat Ukraine, the credibility of U.S. and NATO security guarantees could decline. More countries may accommodate Russia or China. Some might even seek nuclear arsenals. 

Fortunately, Ukraine is holding its own. Russian forces are making only minimal gains in the east. Ukraine has denied Russia air superiority and sunk or scared away most of its Black Sea warships. NATO allies are rushing to emulate Ukraine’s remarkable battlefield innovation. 

Based on its performance, Ukraine may think its defense relationship with the U.S. has not kept pace. A comparative look shows how Ukraine might see potential ways forward for a closer defense relationship.

Treaty alliances and force presence are dimensions in which U.S. ties with some other partners are deeper than with Ukraine. Treaty ties with South Korea have been essential to preserving its armistice with North Korea. Ukraine may view its contribution to countering Russian aggression as of great importance to the alliance, perhaps especially to Poland. Both Ukraine and Poland stand guard against Russian threats to Europe across the central front. 

U.S. force presence in Poland and South Korea raises the cost to Russia and North Korea of any attempt to seize and hold land. Ukraine’s failed counter-offensive in 2023 underlines the urgency of stopping invaders before they dig in and build defensive barriers.  

In the event of a ceasefire, a Western combat presence in Ukraine could be essential to keeping the peace. For this, Ukraine might hope for a U.S. as well as European military presence. Basing it forward may help protect Ukraine from surprise attacks. Some argue for deployment of a “reassurance” force far away from the fighting, but this could negate its deterrent value. 

Ukraine ably integrates and employs advanced U.S. military equipment. Like Poland and South Korea, Ukraine operates Patriot air and missile defenses. Poland is acquiring the stealthy F-35 combat aircraft and South Korea flies them. Ukraine is building an F-16-based force but lacks resources to move up to the F-35. Ukraine may soon receive the U.S. air-launched extended-range attack munition, a cost-effective cruise missile for hitting distant targets. 

Ukraine leads in two areas—uncrewed systems and high-intensity combat experience. Western militaries are scrambling to catch up in developing low-cost precision-strike drones. Operation Spider-Web— a clever attack on airfields across Russia—showed that Ukraine has mastered more than just technology. Ukrainian ground forces are battle-hardened and flexible. They are twice the size of South Korea’s and nearly four times those of Poland. Capable forces could speed Ukraine’s entry into NATO.

For seven decades, the U.S. has forged deep security ties with South Korea, and for three, with Poland. Substantial U.S. defense links with Ukraine are only recent and will take years to develop and mature. But Ukraine’s courageous defense against Russia’s onslaught will encourage Kyiv to seek a deeper U.S. defense relationship that serves both sides’ long-term interests.

William Courtney is an adjunct senior fellow at RAND and a professor of policy analysis at the RAND School of Public Affairs. He was U.S. ambassador to Kazakhstan, Georgia, and the U.S.-USSR commission to implement the Threshold Test Ban Treaty.