“What do ordinary people do when drones with explosives crash into their windows?”

This is the question that civil society groups have been asking for decades, pointing to civilian harm resulting from U.S. drone strikes in the Middle East. It is also the question now posed by Yevgeny Prigozhin, chief of the U.S.-sanctioned paramilitary Wagner Group, about Ukrainian drone strikes in Moscow.

Drones have been used by both sides throughout the Russia-Ukraine War, representing an uptick in drone use in conventional conflicts. In May, Russia accused Ukraine of launching a series of drone strikes in its territory, including attacks targeting President Vladimir Putin’s residence and apartment buildings in a neighborhood in Moscow. The latter strikes, which occurred on May 30, reportedly targeted the homes of senior Russian intelligence officials for the first time in the war.

Ukraine has denied any direct involvement in the attacks. As President Volodymyr Zelenskyy said, “We don’t attack Putin or Moscow. We fight on our territory. We are defending our villages and cities.”

But as Kyiv’s Spring counteroffensive begins, recent reports suggest a network of pro-Ukrainian agents and sympathizers may be responsible for the attacks inside Russia, raising thorny legal and policy questions.

The Biden administration has repeatedly stated it does not want U.S.-provided weapons, including drones, to be used in attacks inside of Russia. National Security Council spokesperson John Kirby reiterated this stance on May 31, affirming that the U.S. government “communicated privately to the Ukrainians, as recently as last week or so, that we don’t want to see U.S.-supplied equipment used to strike inside Russia, that we don’t support attacks inside of Russia and that we are not going to change our policy about not enabling or encouraging those attacks.”

Allied governments in Europe have raised similar concerns, fearing that such attacks could lead to broader escalation and nuclear brinkmanship.

Beyond the risk of escalation, the recent attacks underscore another risk that critics of the U.S. drone program have long feared – that pervasive drone use against suspected terrorist targets in civilian areas will set troubling precedents for allies and adversaries to follow.

Indeed, the targeting of Russian officials who likely do not have a combat role and are not in the military chain of command raises the question of whether states increasingly are adopting the more elastic U.S. military’s definition of “direct participation of hostilities,” where civilians lose their immunity from attack through “effectively and substantially contribut[ing] to an adversary’s ability to conduct or sustain combat operations” (in the words of the Department of Defense’s Law of War Manual).

As the Biden administration meets with Ukrainian counterparts to discuss these incidents, senior administration officials and members of Congress should ask and be satisfied with answers to the following questions:

  1. How are individual targets selected and vetted for drone strikes inside of Russian territory?
  2. What is the approval process for authorizing such strikes? Do civilian or military commanders approve each strike or is this authority delegated to operatives?
  3. Are lawyers in the loop? How so exactly? Do such strikes require their legal approval? What exactly are the legal standards used to define legitimate targets, to define and prohibit indiscriminate attacks, and so forth?
  4. If pro-Ukrainian operatives are conducting drone strikes in civilian areas, what procedures are in place to ensure compliance with International Humanitarian Law and International Human Rights Law?
  5. What legal and policy framework is Ukraine using for accepting responsibility for actions conducted by pro-Ukrainian forces? What legal and policy framework is the United States using for deciding whether to attribute responsibility to Ukraine for actions conducted by pro-Ukrainian forces?
  6. What training do pro-Ukrainian operatives receive and how much latitude do they have in terms of determining the targets, location, and timing of strikes?
  7. Are post-strike assessments conducted to evaluate the accuracy and efficacy of drone strikes conducted in densely-populated civilian areas? What legal and policy standards are used to make those assessments? What is the burden of proof for initial assessments and for final conclusions? Who conducts such assessments?
  8. Does Ukraine rely on any U.S. or allied-provided weapons, intelligence, or logistical support to conduct operations inside of Russia?
  9. Does Ukraine rely on intelligence from joint collection streams with other states in planning or conducting such attacks?
  10. How can Ukraine guarantee that U.S. weapons or intelligence will not be used in such operations when doing so would violate U.S. policies or laws?


While it may be uncomfortable to question belligerents fighting a just war in self-defense – particularly when Ukrainian soldiers have shown a far greater respect for the law than their Russian counterparts – failing to do so risks letting such conduct slide into more egregious behavior.

Image: A “No Drone Zone” sign sits in the Zaryadye park, a short distance from the Kremlin, prohibiting unmanned aerial vehicles flying over central Moscow (Photo by NATALIA KOLESNIKOVA/AFP via Getty Images).