Let’s say for a minute these are drug or terrorist boats.

Wouldn’t it be in the US best interest to capture these, gather proof, gather further intel?

I’m not making an outrageous claim. They are making outrageous claims and destroying the evidence.

People that mold some fiberglass and put some engines in it do not usually put a flag on their thing.

Also, plenty of planes do not fill flight plans, even in international flights.

Not all boats fly a flag. A national flag is not required in may cases. Not all planes file flight plans.