Dropping those Mexican ports is very overdone as those places are safer then some other cities worldwide. I also disagree with crime against tourists. I have been living 5 months in P. vallarta this winter (for the 3rd time during winter) and am in almost daily contact with people in Vallarta. We (and many of our friends) never had any problems, not while shopping, going out to diner, driving our car, taking public transport.
No cruise-passenger was killed as long as I can remember.
I donot say nothing will or can happen, but by using common sense there is no direct danger. People who drink too much or are careless with their belongings might have some problems, but that can happen anywhere.
Puerto Rico is having major drugsproblems, with murders etc., (also not against tourists) but nobody seems to care and ships keep on sailing.