Friday night's Democratic presidential candidates' forum, conducted by Rachel Maddow, had some noteworthy moments for LGBT Americans, especially in Hillary Clinton's defense of her controversial justification of the Defense of Marriage Act.

Clinton stood by her earlier statements that DOMA, signed into law by her husband, Bill, as he was up for reelection in 1996, was a way to head off something worse -- a constitutional amendment banning same-sex marriage.

Several activists and pundits have taken issue with that assertion, saying a constitutional amendment wasn't on the table at the time. But there were "private conversations" about an amendment, Clinton told Maddow.

"The important thing now is that DOMA is gone," Clinton added regarding the law, which prohibited the federal government from recognizing same-sex marriages and allowed states to opt out of recognizing those performed in other states. A 2013 Supreme Court decision struck down the first part, and this year's marriage equality ruling by the high court took care of the rest.

Clinton further noted that it's important to take care of the anti-LGBT discrimination that still exists, as in many states it's still legal to fire someone or deny them housing because of their sexual orientation or gender identity. This week's voter repeal of the LGBT-inclusive Houston Equal Rights Ordinance shows the need to keep fighting for equality, she said.

Of the Houston situation, she noted, "What the far right did very successfully was to engender a lot of fear," with a campaign focusing on fears that allowing transgender people to use the restrooms comporting with their gender identity would somehow enable predatory behavior against women and children -- a theory that has been thoroughly debunked.

Clinton and the other two candidates interviewed by Maddow tonight -- U.S. Sen. Bernie Sanders of Vermont and former Maryland Gov. Martin O'Malley -- all have strongly pro-LGBT records, although they've highlighted their differences on who came to what position the soonest or in the strongest fashion. Sanders and O'Malley also made some supportive statements in tonight's forum, which was not a debate; instead, Maddow interviewed each candidate individually onstage at Winthrop University in Rock Hill, S.C., in the broadcast on her home network, MSNBC.

Sanders spoke of the need to get white working-class voters to return to the Democratic Party, saying that by voting Republican, they're going against their own economic interests. These voters need to know that their enemies aren't gay people or immigrants, but are the monied special interests seeking to keep wealth concentrated at the top of the economic heap, he said.

O'Malley touted his accomplishment in enacting marriage equality legislation in Maryland, and he said young people make him hopeful about the future of the nation, because they don't want to bash immigrants, deny climate change, or deny rights to same-sex couples.

Maddow engaged the candidates on numerous other issues, all in her trademark manner -- as a policy wonk with a sense of humor and a tough journalist who asks pointed questions while remaining respectful.

All three candidates delivered messages of economic populism, which they said would be key to strengthening Democratic support in the South and also address the concerns of marginalized populations. "Our party is the party of opportunity for all," said O'Malley. Sanders, a self-described democratic socialist, called for an end to "our disastrous trade policies" and offshoring of profits, and spoke of the need to persuade companies to invest and create jobs domestically. Clinton said, "People rightly believe that corporations and the powerful have stacked the deck."

Clinton has come under criticism for her ties with those same interests, with Maddow noting the former first lady, senator, and secretary of state had taken some generous speaking fees from Wall Street firms. "Anybody who thinks they can influence what I do doesn't know me very well," Clinton replied. She also said, "I want to be the president for the struggling, the striving, and the successful."

Sanders, for his part, emphasized that his campaign is funded primarily by small donations from individuals and that, unlike Clinton, he has no super PAC working on his behalf.

Maddow questioned, though, how much Sanders differs from Clinton in his policy positions. He recently told The Boston Globe's editorial board, "I disagree with Hillary Clinton on virtually everything." When Maddow queried him about this, he replied, "Virtually is the operative word," but added that campaign financing is a major difference.

On foreign policy, the candidates all agreed that the Iraq war started under George W. Bush's administration was a huge mistake. Sanders, when asked how he'd deal with the terrorist group ISIS in the Middle East, said he wouldn't want to send in U.S. ground troops but would like to see a coalition of Muslim countries take ISIS on, backed by nations from around the world, not just the U.S. "This is a war for the soul of Islam," he said.

When Maddow asked Clinton about her image as the most hawkish of the candidates, Clinton responded that she favors diplomatic solutions to international disputes but can't rule out the use of force.

Maddow pressed O'Malley at his low ranking in the presidential polls -- his support hovers at about 2 percent. "I kind of like a tough fight," he replied, noting that he'd faced similar uphill battles over the course of his career. He touted his record of accomplishments at the executive level in Maryland and in Baltimore, where he was once mayor, as reason to support him.

Also, like his fellow Democrats, he emphasized inclusivity as a measure of difference from the Republican field. "The symbol of America is not a barbed wire fence, it's the Statue of Liberty," he said in a pointed rebuke to Donald Trump's anti-immigrant views.

Gun control, police overreach, and the Keystone pipleine were among other matters that came up with the candidates. In between dealing with serious issues, though, Maddow asked each candidate some questions on the lighter side in the middle of her session with each. She asked O'Malley to name the most impractical item of clothing he owns, which he said is a kilt that had been given to him.

Sanders wondered if she'd want to ask about his underwear or if he's really actor Larry David, referring to a recent Saturday Night Live sendup. Actually, she asked him what his dream job outside of politics would be president of CNN. "The way media deals with politics would change," said Sanders, who had expressed disdain for the media in general, Maddow excepted.

Maddow asked Clinton, if she had to pick a running mate from the current field of Republican candidates, who she would choose. "There are Republicans I could pick, but not one of them," she replied.

Watch clips of Maddow with each candidate below, and find more on the MSNBC website.