Ukraine’s president Volodymyr Zelenskiy has paid a defiant wartime visit to Washington to thank Americans for helping to fund the war against Russia. In a speech to Congress, he said the money is “not charity” but an “investment” in global security and democracy. The whirlwind stop in Washington — his first known trip outside his country since Russia invaded in February — was aimed at reinvigorating support for his country in the US and around the world at a time when there is concern that allies are growing weary of the costly war and its disruption to global food and...