The intensifying enmity between the United States and Russia arising from the war in Ukraine may obscure a fundamental and durable milestone in climate science: One of the most significant pieces of evidence substantiating a shared major security concern—anthropogenic climate change—was the result of United States, French, and Russian cooperation. Ice cores drilled at Russia’s Antarctic Vostok Station provided among the most incontrovertible proof linking human greenhouse gas (GHG) emissions to increasing atmospheric temperatures—over two decades ago.