I think this probably would work. Now I don't think executing them is the ends, but rather a means to the ends. The ends is to instill fear into them because then once they fear you they just don't want mess with drugs in the first place. Like for the past few days since seeing this topic I been looking into stats on countries that execute people for drug crimes, and to my surprise I found that for the most part they don't really even execute that many people. It seems that pretty much once the fear to do or sell drugs is firmly in place you have so little drug use that you pretty much don't even need to have many executions for drug crimes because it becomes so rare for someone to do such a thing in the first place.
Also I think just domestically here in America, totally ignoring comparisons to where this was tried elsewhere in the world, we tried pretty much all the other ideas, and what happened? The problem only got worse! Not only does the direct problem of drug use get worse, but frankly it's not like the liberals loved us any more for all the compromises, all the leniency, all the legalization of "softer" drugs, all the rehab we subsidized, and all the other methods we did for them bending over backwards to appease them. Nope they didn't love us a single lick more, in fact they hate us now more than they ever did before. I mean let's just be real about it, they freaking played us for fools and despitefully used us. So at this point personally I don't really care what President Trump does to them, and yes, in fact I think he might have a valid idea here because to paraphrase President Trump, "what do we have to lose?"