Rick Santorum on Thursday night called repeal of “Don't Ask, Don't Tell” a “tragic social experiment” which he would reverse.

The military policy that banned gay and bisexual troops from serving openly ended on Tuesday, nearly 18 years after its implementation and 9 months after Congress authorized its repeal. More than 13,000 service members were drummed out of the military for violating the policy.

During last night's Fox News/Google GOP presidential debate, Santorum was asked to answer a question submitted online by a gay service member.

“Do you intend to circumvent the progress that has been made for gay and lesbian soldiers in the military?” asked Stephen Hill, who is serving in the Army in Iraq.

Hill's video question was booed by the audience. And in responding, Santorum had to speak over the audience's thunderous applause.

“I would say any type of sexual activity has absolutely no place in the military and the fact that they are making a point to include it as a provision within the military that we are going to recognize a group of people and give them a special privilege in removing 'Don't Ask, Don't Tell' I think tries to inject social policy into the military. And the military's job is to do one thing and that is to defend our country. We need to give the military, which is all volunteer, the ability to do so in a way that is most efficient and protects the men and women in uniform. And I believe this undermines that ability.”

When moderator Megyn Kelly asked what he would do with gay troops such as Stephen Hill who have already come out, Santorum said he would not penalize them for the mistakes of the current administration.

“What we are doing is playing social experimentation with our military right now – that's tragic. I would just say that going forward we would re-institute that policy, if Rick Santorum was president,” Santorum said. “I would not throw them out, because that would be unfair to them because of the policy of this administration.”

“But we would move forward in conformity with what was happening in the past. Which was sex is not an issue, it should not be an issue, leave it alone, keep it to yourself, whether you're heterosexual or homosexual.” (The video is embedded in the right panel of this page.)