Congress should thoroughly investigate the process that led to the approval of money for the WIV and possible gain-of-function research. It should also debate limits on this kind of research in the U.S. and push for international standards. While China is unlikely to budge, its opacity has aroused justifiable suspicion around the world, and the White House should keep the pressure on Beijing and the WHO.

Democrats and much of the media will avoid the topic because Mr. Paul and the populist right have taken up this cause. Such groupthink is what prevented the lab-leak theory from being treated seriously for more than a year. Making the same mistake twice is inexcusable.