Trump has made it appear that retrieving a man being held at his own personal request is so diplomatically complex that it would have stumped both Henry Kissinger and Bill Nye the Science Guy.

At the same time, however, the American Civil Liberties Union and its allies also took a victory lap. Lee Gelernt, the lead counsel for the immigrant plaintiffs in the case and the deputy director of the A.C.L.U.’s Immigrants’ Rights Project said the case represented an important victory.