Rosie O'Donnell has made headlines over the years for getting into heated arguments with celebrities such as Elisabeth Hasselbeck and Donald Trump, but one of the first times the "Queen of Nice" showed her tough side was in an 1999 interview with Tom Selleck about his involvement with the National Rifle Association.

Selleck was appearing on O'Donnell's widely popular talk show The Rosie O'Donnell Show-which premiered 20 years ago this month-to promote his new movie The Love Letter. The actor was on there to plug the film, but in the light of the recent Columbine shooting O'Donnell instead wanted to talk about gun control and a recent ad for the NRA that featured Selleck.

And things got tense. Quickly.

The talk show host pressed Selleck about his involvement with the NRA, asking him why assault weapon can't be outlawed.

"But you can’t say that guns don’t bear a responsibility. Why wouldn’t the NRA be against assault rifles? This is a gun that can shoot five bullets in a second," she said. "This is the gun that those boys [Columbine shooters] brought into the school. Why the NRA wouldn’t say as a matter of compromise, 'we agree, assault weapons are not good?'"

Selleck professed that he is not the face of the NRA, even though he was in an ad for the organization.

"Don’t put words in my mouth. I’m not a spokesperson. Remember how calm you said you’d be? Now you’re questioning my humanity," Selleck calmly told the host.

"Assault weapons threaten the safety of other people. There’s no reason, in my opinion, to have them," O'Donnell added.

Tom: Do you really think the Second Amendment to the Constitution to guarantee hunting and target shooting? Do you really think that’s what the Founding Fathers meant?

Rosie: I think the Second Amendment is in the Constitution so that we can have muskets when the British people come over in 1800. I don’t think it’s in the Constitution to have assault weapons in the year 2000. But I’m wrong? I guess...

Since the interview O'Donnell has apologized for her ambush on Selleck. “In hindsight, if I had to redo [it], I would do it differently,” she told the New York Post in 2012. "He is a kind man, who, for the rest of his life, has to be associated with me and that one event.”

“It was a week after Columbine,” she added. “I was not really in my best place emotionally. So I do feel bad for him — not for him, but for the way that whole thing played out in that he still has to sometimes answer for it, which I don’t think is fair.”

O'Donnell regretted the way it played out, but another television personality, MSNBC's Lawerence O'Donnell actually thought Rosie had a point in questioning Selleck's involvement with the NRA-especially after the Virginia Tech shooting in 2012:

Whether O'Donnell was correct in blindsiding Selleck with a discussion over gun control in front of an entire viewing audience is not the point. The point is that it's sad that Americans are still having this heated debate almost two decades later and nothing has changed.

"I was meant to bring up the subject as it is in the consciousness of so many today," O'Donnell said as she wrapped up her interview with Selleck. "I thought I would give you an opportunity to discuss your side of it. Which is what I hope that I did. And if I was wrong I’m sorry."

"Well, obviously, it didn’t do much good," the talk show host concluded.

Sadly, it didn't.