It may sound wrong but I am all for this action even if it sounds extreme. If they have the intelligence then surely this is guaranteeing those drugs and those trafficking are removed permanently. I have seen photos of the zombie like drug addicts and the carnage this is causing on US soil so I think they have the right to protect their people by whatever means necessary. The dug cartels must be using other routes to transport their drugs and this cannot be just it. The CIA previously was mixed up with the cartels so the Navy doing the shooting is a far better option I guess. I do not think this is harsh, but more of a necessity in todays world.
But what kind of intelligence do they have? When they were deporting "criminals" out of the US, they were also deporting people who had no criminal record. And that is within the US. How good is their intel?
I'd say, there was department overlap :)