Oman's role in supporting the Iran-backed Houthi rebels in Yemen has prolonged the war, threatened international trade routes, and put American strategic interests at risk. The United States must hold Oman accountable and take diplomatic, economic, and intelligence-sharing measures to address its support for the Houthis. This includes reinforcing the message that support for the Houthis will not be tolerated, implementing targeted economic measures, ramping up interdiction efforts to disrupt arms shipments, increasing oversight of Oman's financial system, and imposing conditionality on military and economic aid. The US should also work with regional allies to develop alternative logistical and trade routes that reduce reliance on Omani ports and land routes.