I've heard different things. I'm going to see my fiance in Japan in October, and I'm trying to get my passport, but I'm afraid I might not be able to get it in time. Is it possible to just use my ID and leave chit?
You still need a passport. If you have military orders to Japan, you would still need a passport. With orders it can be a government passport, it's better to have a regular passport, that way you can go on vacation to most places in Asia without a visa, for up to 90 days.