The Trump administration has built up a fleet of warships near Venezuela, including the largest U.S. aircraft carrier, as American forces keep blowing up small boats accused of smuggling narcotics for drug cartels.

U.S. Southern Command announced that it had conducted another strike against a small boat in the eastern Pacific Ocean on Thursday, following a pause of almost three weeks.

Some of the people viewing the video thought the waving by the survivors could have been an attempt to surrender, which could raise questions about whether the military had violated the rules of armed...