President Donald Trump leaves the stage after speaking at the Republican midterm convention in Dallas, Sept. 9, 2026. (Damon Winter/The New York Times) By THE EDITORIAL BOARD Since President Donald Trump returned to the White House last year, he has vacillated between appeasing President Vladimir Putin of Russia and reluctantly helping Ukraine defend itself against Putin’s invasion. Over the past two weeks, Trump has taken a sharp turn toward appeasement. Desperate to reduce gas prices before…