I guess it depends on where you cruise, but we personally would NEVER wear anything to affiliate us with the military on foreign soil. Even so, we are not allowed to wear the uniform off-base even if driving straight home!
Don't get me wrong, we are very proud to serve our country. It's just that for OPSEC reasons and to avoid those that are Bush-bashers. It seems the first thing someone says after knowing you are military is related to Bush, the war(s), or anything else controversial. While we do get a lot of "thanks" and praise for being military as a couple, it's nice to be on vacation
and not worry about somebody else's dislikes of our great country.
Just my two cents