It's a war crime to execute suspected drug smugglers, or even to execute instead of trial someone found in possession of a large amount of drugs. There is no possible identification of anyone on board or even boat owner from high altitude.

Furthermore, many of the strikes are on speedboats that are going fast enough to plane over the water. It is impossible for any boat to go that fast with enough fuel to get to Florida, and the open cockpit boats themselves look obviously empty. This is simply, provably, pure terrorist evil.