The U.S. acquired the rights to build and operate the canal in the early 20th century, but at the time, Panama was in the process of seceding from Colombia, whose senate was refusing to ratify a treaty that would allow the canal to be built, according to the State Department's Office of the Historian .

Unless he goes to war with Panama, Trump can’t reassert control over a canal the U.S. agreed to cede in the 1970s.