Bill Clinton was interrupted several times Thursday by gay activists during a speech prompting the former president to deliver an impassioned defense of his decision making on gay issues while president before railing against the military's gay ban.

Speaking at the fourth annual Netroots Nation convention in Pittsburgh, Clinton said the nation has “entered a new era of progressive politics” that could last decades if measures such as health care reform can be passed by Democrats.

“We have entered a new era of progressive politics which, if we do it right, can last 30 or 40 years,” Clinton said. “America has rapidly moved to another place on a lot of other issues.”

Clinton, whose speech Thursday stuck mostly to health care and climate change reform, signed into law the Defense of Marriage Act (DOMA), the law that allows states to ignore legal gay marriage and defines marriage as a heterosexual union for the federal government, and “don't ask, don't tell,” the law that prescribes discharge for gay and lesbian service members who do not remain celibate or closeted.

When gay activists challenged Clinton on the military's ban on open gay service, he became a bit ruffled, saying that the public failed to get him support in Congress. “Now that's the truth. That's the truth.”

“They [Congress] were about to vote for the old policy by margins exceeding 80 percent in the House and exceeding 70 percent in the Senate. They gave test votes out there to send me a message that they were going to reverse any attempt I made by executive order to force them to accept gays in the military. Let me remind you that the public opinion now is more strongly in our favor than it was 16 years ago.”

Clinton also pointed out that Congress nixed the “don't pursue” portion of his compromise.

“We will not pursue anyone, any military members out of uniforms will be free to march in gay rights parades, go to gay bars, go to political meetings. Whatever mailings they get, whatever they do in their private lives – none of this will be a basis for dismissal. It all turned out to be a fraud because of the enormous reaction against it among the mid-level officers and down after it was promulgated and [Colin] Powell was gone.”

“Nobody regrets how this was implemented any more than I do. … I hated what happened. I regret it.” he said.

“I think it's ridiculous,” Clinton said, referring to the amount of money wasted ferreting out gay members of the military.

“This policy should be changed,” he added.

Last month, Clinton also endorsed gay marriage, a flip from his long-standing civil unions position.