Defending Ukraine

Russian President Vladimir Putin’s invasion of Ukraine has killed thousands,  and driven more than two million Ukrainians to flee to surrounding countries.  Ukrainian forces have mounted a stiffer defense than analysts predicted, but observers fear this will not last. Paradoxically, the longer Ukrainian forces frustrate Putin’s offensive, the greater the chance that he will resort to indiscriminate attacks on civilian centers. Moreover, the possibility remains that the Kremlin will resort to using weapons of mass destruction to achieve victory. As the war continues, it could spill over or lead Putin to expand his ambitions into neighboring countries. Many of the countries adjacent to this conflict are members of the North Atlantic Treaty Organization (NATO)— an alliance of thirty North American and European democracies who have committed to mutual defense in the event of an attack. This would precipitate a broader war between NATO and Russia that could cause mass devastation in Europe and have worldwide ripple effects. At the extreme, such a war risks a catastrophic nuclear exchange.

The United States and NATO have an urgent interest in assisting Ukraine and keeping the fighting confined within its borders. So far, the U.S. and NATO response has focused on indirect measures, imposing crippling economic sanctions and supplying Ukraine with billions of dollars’ worth of weapons . This strategy could increase the price of Putin’s invasion to the point where he would consider negotiating a ceasefire. The hope is that sanctions and aid will not provoke Russian retaliation. As the war grows deadlier, however, calls for more direct intervention have grown. Many policymakers doubt arms transfers are sufficient to turn the tide in Ukraine. Others—especially in the Baltic countries on NATO’S eastern flank— also fear that escalation is inevitable. Former Soviet republics believe that the conflict will spread if not from an inadvertent spillover from Ukraine, then from Putin’s imperial ambitions.. Moreover, Russian forces have suffered early setbacks in their invasion, sparking speculation that they are not as strong as initial analyses suggested. If these assessments are true, intervening before a NATO ally is attacked could give the United States a decisive advantage. An intervention would allow the United States to stop Russia in its tracks and guarantee the safety of nearby NATO members.

Two principal options for a direct intervention exist. The first is to commit to the full-scale defense of Ukraine by deploying ground troops to the country. If assumptions about Russian forces’ weaknesses prove true, this option offers the strongest defense to Ukraine and could safeguard neighboring NATO members’ security. Yet this would trigger the very war that NATO hoped to deter. At best, this option still puts thousands of U.S. service members at risk. If it goes wrong, it could lead to a devastating land war in Europe. At worst, direct U.S. involvement could drive Putin to resort to a nuclear attack. The second option is to support Ukraine by establishing a no-fly zone over Ukraine's airspace. This would prevent Russian airstrikes and rob Russia of one of its chief military advantages. However, Russia is unlikely to simply abide by a no-fly zone. NATO air forces would need to enforce it by directly targeting Russian planes and air defense systems. Therefore, even this limited option would likely amount to a NATO war with Russia . Critics of the idea add that, on top of its risks, a no-fly zone fails to curb Russian forces from bombarding Ukrainian targets with ground artillery. So far, NATO countries have taken any form of direct military response off the table. But as the war in Ukraine drags on, policymakers need to carefully consider how they can help defend Ukraine, while minimizing the risks of triggering a far more devastating war.