The Trump administration is ending one of the most important elements of U.S. military assistance to the Saudi-led war in Yemen: the refueling of Saudi warplanes. The Nov. 10 announcement is part of the White House response to the killing of dissident Saudi journalist Jamal Khashoggi and follows appeals for a ceasefire in the war that Riyadh and its allies have been waging against Iran-backed Houthi rebels since March 2015.

So far, the Saudis and their partners, especially the United Arab Emirates, have responded to calls for a ceasefire with more war. The Saudi-led alliance renewed its offensive against the port city of Hodeidah, which is the entry point for 80 percent of Yemen's food, fuel and other imports. Already, half of Yemen's 28 million people are on the brink of starvation, and the United Nations has warned that disruption to the port at Hodeidah could trigger a large-scale famine.

But ending the mid-air refueling of Saudi aircraft is not enough to stop the conflict. In addition to refueling warplanes and providing intelligence assistance, the United States has rushed billions of dollars' worth of missiles, bombs and spare parts to help the Saudi military continue its bombing campaign, starting under President Barack Obama. Yet neither the Obama nor Trump administrations put enough pressure on the Saudis to negotiate a political settlement with the Houthis to end the war.