When President Donald Trump took the stage in Egypt to hail the U.S.-brokered ceasefire deal between Israel and Hamas, a row of world leaders stood behind him like extras in a political drama. European governments have struggled to play a significant role in diplomacy over the Gaza war, while the “America First” leader has played a central one, pushing longtime allies in Europe toward the sidelines. Closer to home, they have labored with mixed results to shape Trump’s response to Russian President Vladimir Putin's obstinate pursuit of the Ukraine war, a conflict with profound consequences for the continent’s future.