Officers and Enlisted go on liberty in foreign ports without passports whether they are in uniform or not.
Military ID and orders are sufficient when on official business in other countries, but when you're traveling on leave and in civilian attire, you typically need to have a (tourist) passport. There are of course, no-fee military passports as well. Those are treated the same as Military ID and a copy of orders. As soon as you stop traveling for official business and start traveling for leisure, you have to switch from the no-fee military passport to the tourist passport.
Tragic. None of those douchebags could have taken him outside that context. There’s a memorial to him next to Arlington.It was Bob Stethem. They named an Arleigh Burke destroyer after him.