Just watched an SNL skit in which they referred to them as fishing boats. Pretty sure you’re off base with what most people think, it’s not an unreasonable fringe stance. On average people are going to care more about the idea that “we” just killed a several dozen random fishermen off the coast of a country we’re not even at war with than the idea that um well actually narcotraficantes are people too and deserve a trial by jury. I don’t really see them anymore, but I used to regularly see ‘shoot your local heroin dealer’ bumper stickers. Talking with ex military coworkers, though, there plenty of criticism of these murders, and plenty of distrust in the brass. That’s all I’ve got to say, though, you’re just kneecapping your effectiveness by not even bothering to recognize the glaring uncertainty about who these victims were.

It’s reasonable to expect some form of evidence that the victims actually committed a crime.

You’re right that even if* they were criminals it would still be murder, but there are a lot of authoritarians out there who are perfectly willing to prescribe death penalties for any alleged crime. Going with your tact and forfeiting any need to prove that the victims actually did anything wrong is a weaker argument. Keep in mind, we don’t actually have any evidence that they are what the regime says they are, them " looking like what a drug smuggling boat would look like" is incredibly tenuous.