The U.S. Army prohibits troops married to each other, when overseas, from being alone together, kissing or showing any PDA (Public Displays of Affection.) Violations can be punished by court martial. Unmarried troops are also forbidden to engage in this sort of behavior. Last year, a female reservist, serving near her husband in Iraq, had enough, and fired off an email to her congressman. As a result, the army "relaxed" the rules. As a practical matter, there is a lot of sex between troops (with many pregnancies to prove it), although they know better than to engage in a lot of PDA. The unofficial army policy is to let it go if the sexual escapades of the troops don't get into the news and embarrass the brass (which can do serious damage to a commanders career).