If even a fraction of this is true then why would one volunteer for the US military?

The most appealing explanation lies in the motives of those driving this ostensibly schizophrenic conduct. Plainly, they view sexual morals as something to be manipulated for the accomplishment of political objectives. Hence, lewd and offensive sexual conduct can be deliberately used as a tactic against detainees. On the other hand, officers who earn the leadership’s ire will be humiliated and disgraced using innuendo of sexual misconduct as a tactic.
The cynicism and immorality of this mindset is staggering. It reflects a wholesale repudiation of traditional military values.
One can well question the efficacy of sexual humiliation practices as tools for interrogation and intelligence gathering. However, no one can question their highly inflammatory effect in the War on Terror: they tarnish America’s reputation and put our soldiers at risk. And they may well claim another victim. Experts are already noting that at Rumsfeld’s current burn rate, the volunteer army cannot be sustained much longer. Rumsfeld’s cynical sexual policies are destroying military morale and discipline and hastening the volunteer army’s demise.

Yep, why would anyone volunteer for this environment? Unless, well, they think they might like it….
Read all of Scott Horton’s post: Sexual Perversion in Rumsfeld’s Pentagon.