Specifically...considering they do not grow that crap onboard you would have to smuggle it onboard somehow and if you are caught you will go to jail, simple. Do not think it can't happen as I have personally seen more than one person stopped and searched and arrested trying to board with illegal drugs. Drug penalties in the islands are very severe and could result in many years behind bars for even a small amount. In addition their prisons are horrific and you will need quite a bit of money sent to you to even survive inside one of those places so that you can eat or attend to even the barest of necessities. Bottom line, it is beyond stupid to even try.