Putin is planning for this war to continue. That leaves two key questions for Ukraine’s European alliesDavid Shimer was the director for eastern Europe and Ukraine on Joe Biden’s National Security CouncilThe war between Russia and Ukraine is approaching a historic turning point: unless the Trump administration adjusts course, US military aid for Ukraine is about to cease.In the months before leaving office, Joe Biden made a series of decisions to augment Ukraine’s stockpiles of vital munitions. Toward the end of 2024, the Department of Defense surged hundreds of thousands of artillery rounds, thousands of rockets and hundreds of armored vehicles to Ukraine, and that December, he approved an additional $1.25bn security assistance package for Ukraine, which has enabled the continued flow of US arms ever since (with the exception of the damaging pause ordered by Donald Trump in March).David Shimer served on the White House national security council from 2021-25, including as the director for eastern Europe and Ukraine and as director for Russian affairs. He is an adjunct senior research scholar at the Institute of Global Politics at Columbia University’s School of International and Public Affairs. Continue reading...