Increased energy trade has important economic and strategic significance for the United States and Mexico. Mexico’s energy-market reforms that opened access and improved natural gas trade between American producers and Mexican consumers have been beneficial for citizens in both countries. President López Obrador’s desire to return to energy nationalism threatens those gains. Both the U.S. and Mexico should commit to policies and regulations that continue to open access to markets, improve transparency, and expand opportunities for investment. Doing so will benefit both Americans and Mexicans.