While it already feels like it happened ages ago, last week, British Prime Minister Theresa May declared the poisoning of former Russian spy Sergei Skripal on British soil to be an “unlawful use of force by the Russian state against the United Kingdom.” But what exactly does that declaration mean, and how is the UK entitled to respond under international law to such an “unlawful use of force”?

On this week’s podcast, Rebecca Ingber, an associate professor at Boston University School of Law and a former State Department attorney, told me that it’s just as important to listen to what May didn’t say, as what she did. May chose her words extremely carefully. She didn’t call the poisoning an “armed attack,” which would have unambiguously triggered the UK’s right to use force in self-defense under the UN Charter. Rather, the “use of force” left the British government plenty of room to maneuver under international law a way that could implicate any number of possibilities.


Photo by Toby Melville – WPA Pool/Getty Images