Tuesday during CNN’s Republican presidential debate, Republican presidential candidates Donald Trump and Jeb Bush sparred for a second time over the “seriousness” of Trump’s candidacy and proposals.

Exchange as follows:

TRUMP: We have to be much tougher and much stronger than we’ve been. We have people that know what is going on. You look at the attack in California the other day, numerous people, including the mother that knew what was going on. They saw a pipe bomb sitting all over the floor. They saw ammunition all over the place. They knew exactly what was going on. When you had the World Trade Center go, people were put into planes that were friends, family, girlfriends and they were put on planes and they knew what was going on. They went home and wanted to watch their boyfriends on television. I would be very, very firm with families. Frankly, that will make people think because they may not care much about their lives. But they do care, believe it or not, about their families’ lives.

BUSH: This is another example of the lack of seriousness. Look, this is, this is troubling because we’re at war. They’ve declared war on us and we need to have a serious strategy to destroy ISIS, but the idea that that is a solution to this is just crazy. It makes no sense to suggest this. Look, two months ago Donald Trump said that ISIS was not our fight. Just two months ago, he said that Hillary Clinton would be a great negotiator with Iran, and he gets his foreign policy experience from the shows. That is not a serious kind of candidate. We need someone that thinks this through. That can lead our country to safety and security.

TRUMP: Look, the problem is we need toughness. Honestly. I think Jeb is a very nice person. He’s a very nice person, but we need tough people and we need toughness and we need intelligence and we need tough. Jeb said when they come across the southern border they come as an act of love,

BUSH: You said on September 30 that ISIS was not a factor.

TRUMP: Are you talking or am I talking? You can go back. You interrupted me. Are you going to apologize?

BUSH: I’m talking right now…a little of your own medicine

TRUMP: I know you are trying to build up your energy but its not working.

Am I allowed to finish? Excuse me, am I allowed to finish?… look, look, look. We need a toughness. We need strength. We’re not respected, you know, as a nation any more. We don’t have that level of respect that we need and if we don’t get it back fast, we’re just going to go weaker, weaker and just disintegrate. And we can’t allow that to happen. We need strength. We don’t have it. When Jeb comes out and he talks about the border and I saw it and I was witness to it and so was everyone else and I was standing there, they come across as an act of love. He’s saying the same thing right now with radical Islam. And we can’t have that in our country. It just won’t work. We need strength.

BUSH: Donald, you’re not going to be able to insult your way to the presidency. That’s not going to happen. And I do have the strength. Leadership, leadership is not, leadership is not about attacking people and discouraging people. Leadership is about creating a serious strategy to deal with the threat of our time. I laid out that strategy before the attacks in Paris and before the attacks in San Bernardino. And it is the way forward. We need to increase our military spending. We need to deal with the no-fly zone in Syria and building a military that is second to none.

TRUMP: With Jeb’s attitude, we will never be great again. That I can tell you. We will never be great again.

Follow Pam Key on Twitter @pamkeyNEN