As diesel prices reach unprecedented heights in the United States, Donald Trump has thrown his support behind a ban on fuel exports — a posture that marks a meaningful turn away from the free-trade energy orthodoxy that has long shaped American policy. The move reflects an ancient tension between global commerce and domestic welfare, between the logic of open markets and the political reality that citizens feel price spikes in their bones. Whether such a restriction would genuinely ease the burden or simply redistribute it across global markets remains an open and consequential question.