It's probably for security reasons--"loose lips sink ships". But I've talked to other military folks on FR, one was in South Korea and another was in Iraq, or so he claimed. He seemed to know what he was talking about, but who knows?
When beloved spent a year in Korea he took the family computer. He could access FR etc when he was not at work. He was able to access AOL mail until someone abused something and it was put off limits.
Yes security is the reason.
I suppose all I can say is I hope we can get the truth out to whoever will listen.