In the past year or more, the military has tested new ports and bases as options to use in the event of conflict with Iran

President-elect Joe Biden has said he plans for the U.S. to re-enter the Iran nuclear deal he helped establish under the Obama administration in 2015. WSJ’s Gerald F. Seib explains why doing so won’t be as simple as it sounds. Photo: Abedin Taherkenareh/Shutterstock