The notable moments from the fifth GOP debate

The top Republican presidential candidates duked it out on CNN's main stage for nearly three hours Tuesday night, slinging out one-liners but also engaging in substantive policy debates on immigration, national security, and foreign policy issues.

From Donald Trump's proposal to close the internet to terrorists, to Kentucky Sen. Rand Paul's harsh attack on Chris Christie as the candidate most likely to start World War III, here are some of the notable quotes of the night:

Donald Trump:

  • On blocking the ISIS from the internet: "ISIS is recruiting through the Internet. ISIS is using the Internet better than we are using the Internet, and it was our idea. What I wanted to do is I wanted to get our brilliant people from Silicon Valley and other places and figure out a way that ISIS cannot do what they're doing....I would certainly be open to closing areas where we are at war with somebody. I sure as hell don't want to let people that want to kill us and kill our nation use our Internet."
  • On CNN's debate questions: "I think it's very sad that CNN leads Jeb Bush, Governor Bush, down a road by starting off virtually all the questions, 'Mr. Trump this, Mister' -- I think it's very sad...But I thought it was very unfair that virtually the entire early portion of the debate was Trump this, Trump that, in order to get ratings, I guess."
  • On Jeb Bush, sarcastically: "Oh, I know. You're a tough guy, Jeb. I know."

Ben Carson:

  • On political correctness and surveillance: "We need to make sure that any place, I don't care whether it's a mosque, a school...if there are a lot of people engaging there in radicalizing activities, then we need to be suspicious of it, we need to get rid of all this P.C. stuff."

Marco Rubio:

  • Response to Ted Cruz's idea to defeat ISIS with air power: "You can't carpet-bomb ISIS if you don't have planes and bombs to attack them with. And if we continue those cuts that we're doing now... we are going to be left with the oldest and the smallest Air Force this country has ever had."
  • Cruz's support of the USA Freedom Act, which stripped the NSA of its bulk metadata collection powers: "We need more tools, not less tools. And that tool we lost, the metadata program, was a valuable tool that we no longer have at our disposal...I promise you, the next time there is attack on -- an attack on this country, the first thing people are going to want to know is, why didn't we know about it and why didn't we stop it? And the answer better not be because we didn't have access to records or information that would have allowed us to identify these killers before they attacked."
  • Immigration, path to citizenship: "I am personally open -- after all that has happened and after ten years in that probationary status where all they have is a permit, I personally am open to allowing people to apply for a green card."

Ted Cruz:

  • Defending Trump: "Everyone understands why Donald has suggested what he has. We're looking at a president who's engaged in this double-speak where he doesn't call radical Islamic terrorism by its name. Indeed, he gives a speech after the San Bernardino attack where his approach is to try to go after the constitutional rights of law-abiding citizens rather than to keep us safe."
  • During an argument with Rubio about undocumented immigration: "We will build a wall that works, and I'll get Donald Trump to pay for it."

Jeb Bush:

  • The top Facebook moment was Bush's jab at Trump: "Donald, you're not going to be able to insult your way to the presidency. That's not going to happen... Leadership is not about attacking people and disparaging people. Leadership is about creating a serious strategy to deal with the threat of our time."
  • Earlier, Bush also hit Trump as a "chaos" candidate: "Donald, you know, is great at the one liners but he's a chaos candidate and he'd be a chaos president. He would not be the commander-in-chief we need to keep our country safe."

Carly Fiorina:

  • On refusing to speak with Vladimir Putin: "I didn't say I would cut off all communication with Putin. What I said was as president of the United States, now is not the time to talk with him... There is a time and a place for everything. There is a time and a place for talk. And there is a time and a place for action."

John Kasich:

  • On Putin: "Frankly, it's time we punch the Russians in the nose. They've gotten away with too much in this world."

Chris Christie:

  • On no-fly zones in Syria: "Yes, we would shoot down the planes of Russian pilots if they were stupid enough to think that this president is the same feckless weakling that the president we have in the Oval Office is right now."

Rand Paul:

  • Response to Christie's comment, above: "I think if you're in favor of World War III, you have your candidate."