At this time, we have absolutely no legal reason to do such a thing. We actually have no legal standing in blowing boats out of the water in international waters, either.
What SHOULD be happening is to allow those boats to make it into the 3-mile limit, then stop them, to prove intent to deliver, and then sink them, with the occupants aboard. In that way, there'll be proof that they were fully intending to distribute harmful substances into the U.S., and the message will be clear........do not do this again.
If "diplomatic" discussion with Madura doesn't net some appreciable results, or is rejected at the outset, then we MIGHT have some legal standing at invasion, only AFTER a congress-supported declaration of war.
That's how our system is supposed to work.....let's try to keep it that way.
Roger