A 15 second passionate kissing scene, but not necessarily offensive.

No gore.

Plenty of wartime shooting and deaths, expected of a WWII movie. Only a very few scenes display blood.

About a dozen mild expletives, including SOB (2x), ass, hell, damn (6x), including about 6 religious terms.

cigarette smoking

Several cigarette smoking scenes, common in WWII era.

A scene of a badly burned alien might be too intense for some.