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Five big takeaways from the GOP debate

Updated

Las Vegas – There were big fights on Tuesday night in Las Vegas, some meaty policy exchanges and a much-anticipated conflict that never materialized. Here are the big takeaways from the last Republican debate of the year.

Jeb made the most of it

Former Florida Gov. Jeb Bush may look down and out in the polls, but on Tuesday he at least boasted a solid debate in which he tangled repeatedly with Donald Trump and lived to tell the tale. The turn toward national security seemed to suit Bush, whose core message was that Trump was a “chaos candidate” who would be a “chaos president.”

The Last Word with Lawrence O’Donnell, 12/15/15, 10:00 PM ET

Jeb Bush: Trump is a 'chaos candidate'

Donald Trump’s call to ban Muslims from entering the United States dominated the fifth Republican debate in Las Vegas. Jeb Bush took aim at Trump, while Rand Paul and Ted Cruz sparred with Marco Rubio over metadata collection. Lawrence talks with Stuart S

“Donald, you’re not going to be able to insult your way to the presidency,” Bush said at one point.

Trump got in his usual barbs about Bush’s poll numbers and energy level, and some surely stung. “You’re a tough guy, Jeb, you’re real tough,” Trump told his rival. “Well let’s see, I am at 42% and you’re at 3, so, so far I’m doing better.”

RELATED: Trump soothes Republican fear, pledges to remain in GOP

But Bush didn’t seem fazed and stuck to a consistent strategy of attacking Trump’s proposals on raw efficacy, rather than principle. Most notably, he argued that a Muslim travel ban would alienate Muslim allies abroad who are needed to fight ISIS rather than raise concerns about discrimination or religious freedom.

Trump, for his part, helped make Bush’s case by stumbling on a question about how he would manage the nuclear triad(America’s land/sea/air nuclear strike capability). Trump appeared not to recognize the phrase and started talking about Iraq and Syria before finally responding, “I think, for me, nuclear is just, the power, the devastation is very important to me.”

That type of ignorance has never hurt him with his supporters before, but it surely was satisfying for Bush to watch.

Rubio forced Cruz to the right 

The dominant – and likely most consequential – rivalry of the night was between Sens. Marco Rubio and Ted Cruz.

The two have been battling on the campaign trail for weeks over national security and those arguments carried over to the debate. But by far the most significant exchange was over immigration.

The presidential campaign: Marco Rubio
Because of his youth and relatively moderate campaign rhetoric, Rubio is often touted as the Republican Party’s best hope of appealing to younger voters.
Cruz, as he has done recently, laid into Rubio for supporting “amnesty” through his bipartisan immigration bill. Rubio shot back that their current positions were similar given that Cruz had for months refused to rule out eventual legal status for undocumented immigrants (although not citizenship).

“Does Ted Cruz rule out ever legalizing people that are in this country illegally now?” Rubio asked, trying to corner his rival.

“I have never supported legalization,” Cruz said. “I have never supported legalization, and I do not intend to support legalization.”

That was the furthest Cruz had gone and it appeared to tie him decisively in the “self-deportation” strategy Mitt Romney backed in 2012 en route to a 27% showing with Latino voters.

Rubio’s team accused Cruz of hedging again, focusing on the word “intend,” but Cruz’s campaign chair Chad Sweet confirmed to the press afterward that the issue was settled.

“Sen. Cruz unequivocally  – unequivocally – does not support legalization,” Sweet said. Instead, Cruz favored “attrition through enforcement,” a concept virtually identical to self-deportation.

“We don’t choose to use that phraseology,” Sweet said when asked about the comparison.

Cruz defused Trump

If there’s one thing Trump’s good at it’s confounding conventional wisdom. Much of the pre-debate coverage focused on an expected conflict between Trump and Cruz, who Trump attacked as a “maniac” in the Senate this week and criticized for talking behind his back at a fundraiser in which Cruz questioned his “judgment” on foreign policy.

Cruz desperately tried to repair the rift and it looks like his efforts paid off: The two were buddy-buddy the whole night.

12/15/15, 10:50 PM ET

Donald Trump changes tune on Cruz: 'He's just fine.'

Donald Trump, asked in Tuesday’s debate how he apparently drastically changed his regard for Ted Cruz, explains that in three or four days of getting to know Cruz, ‘He’s just fine. Don’t worry about it.’

“Let me just say that I have gotten to know him over the last three or four days. He has a wonderful temperament,” Trump said when asked about his “maniac” line. He followed up with a joking-but-not-really-joking warning to Cruz of, “You better not attack.”

Cruz, for his part, completely ducked a question on why he was willing to criticize Trump in private fundraisers but not in public. He seems to have bought a reprieve for his efforts. We’ll see how long it lasts with the two increasingly looking like the front-runners.

RELATED: Cruz: ‘I do not intend to support’ pathway to legalization

To dictator or not to dictator

The most substantive disagreement between the candidates was over the question of regime change. Cruz, Paul and Trump all criticized their rivals for supporting interventions in Libya before and Syria today to depose dictators, arguing that such interventions opened the door for chaos and radical Islamic groups.

“I believe in an America-first foreign policy,” Cruz said.

12/15/15, 10:04 PM ET

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“When we toppled Gadhafi in Libya, I think that was a mistake,” Paul said. “I think ISIS grew stronger, we had a failed state, and we were more at risk.”

Rubio, by contrast, defended his support for the Libya intervention, which he said shortened an already active civil war that could have produced even worse consequences, and reiterated his call to remove Syrian dictator Bashar al-Assad.

“He has been so brutal toward the Sunni within Syria that he created the space that led to the people of Syria themselves to stand up and try to overthrow him,” Rubio said. “That led to the chaos which allowed ISIS to come in and take advantage of that situation and grow more powerful.”

Chris Christie’s new pitch

New Jersey Gov. Chris Christie, rising in the polls in New Hampshire, seemed to take well rhetorically to the national security emphasis and put a lot of stock in his career as a U.S. attorney prosecuting terrorists.

“I’m a former federal prosecutor. I’ve fought terrorists and won and when we get back in the White House we will fight terrorists and win again and America will be safe,” Christie said.

12/15/15, 10:13 PM ET

Paul invokes 'Bridgegate' at GOP debate

While debating a no-fly zone over Syria, Rand Paul made a dig at fellow GOP candidate Chris Christie over the “Bridgegate” scandal, which drew jeers from the audience.

He had some flubs: At one point he talked about his plan to work with “King Hussein” of Jordan, who is dead and has been replaced by King Abdullah II. Christie strategist Mike DuHaime told MSNBC afterward the governor “misspoke” and noted that Christie knows Abdullah personally. But overall he sounded confident positioning himself as someone who had personal experience on security and his argument might fit the post-Paris, post-San Bernardino times for GOP voters. 

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Five big takeaways from the GOP debate

Updated