I dont think anyone wakes up decides 'hmm, I think I'll be gay today, since its socially acceptable now'.
It isnt a lifestyle choice, you cant help being gay anymore than you can help being black, white,tall or short- its the way you are born; just takes some people longer to realise & admit to it than others, for obvious reaosns I would hope.
As for letting homosexuals serve in the military, why not? Just so long as they dont start wearing pink bandanas as muslim insurgents would have a field day...