By Sahil Kapur, Bloomberg News (TNS)

WASHINGTON — Deadly attacks Friday night by the Islamic State in Paris have thrust foreign policy to the forefront of the 2016 presidential debate in the United States, providing an important gut-check moment for Republican voters who rank outsiders Donald Trump and Ben Carson as their top choices.

One school of thought among Republican strategists is that the new focus could benefit Trump, whom GOP voters trust most on foreign policy. In a Reuters poll released in November, 41 percent picked Trump as their favorite candidate to conduct foreign policy, while 39 percent picked Carson. Sen. Marco Rubio came in third place with 31 percent. Republican voters said they trust Carson most to handle nuclear weapons, followed by Trump, and with Rubio in third.

According to this theory, Trump’s unparalleled knack for bravado — exemplified by his vow in Iowa to “bomb the shit out of” ISIS one day before the Paris attacks — could further endear him to conservative voters, despite his lack of experience on foreign policy.

“Many of us have said that national security policy needs to be central to the elections. Paris only makes that more clear,” said Danielle Pletka, a national security and foreign policy hawk who works at the conservative American Enterprise Institute. “Trump is a candidate for people who think reality TV is reality. Perhaps when they see the faces of the dead, they will realize that in real life, slogans don’t save people. Sound policy does.”

Rubio, Sen. Ted Cruz and Jeb Bush — who round out the top five current polling leaders in the GOP field — are trying to seize the moment and show their foreign policy chops.

Bush cast doubt Sunday on whether Trump or Carson can be trusted to be commander-in-chief. “The words that I hear them speaking give me some concern,” he said on NBC’s “Meet The Press.”

Carson didn’t help himself in a “Fox News Sunday” interview, when he was unable to name any countries he’d include in an international coalition he has called for to go after Islamic State militarily.

“This reframes the candidate choice in the eyes of many voters,” said Kevin Madden, a senior adviser and spokesman for Republican nominee Mitt Romney’s 2012 campaign. “This race could potentially swing away from candidates who were offering the outsider argument and instead swing toward those candidates touting a more serious and substantive agenda with regard to national security and foreign policy.”

On Sunday, Rubio, who sits on the Senate Foreign Relations Committee, said the U.S. “won’t be able to take more refugees,” because “there’s no way to background check someone that’s coming from Syria.” (In September, he said told Boston Herald radio he “would be open to” taking in more refugees provided terrorists were screened out.) The Florida senator, who has made hawkish foreign policy a centerpiece of his campaign, also called for invoking Article 5 of the NATO agreement to deem the Paris attack an act of war and fight back collectively.

Cruz said Saturday on Fox News that it “makes no sense whatsoever” to bring in Syrian refugees to the United States, given that “our intelligence cannot determine if they are terrorists here to kill us or not.” He also said that “our enemies are not tired of killing us. This will be coming to America. ISIS plans to bring these acts of terror to America.”

Immigration is also weaving its way into the national security debate, with some Republican candidates channeling the base’s wariness of immigration reform by connecting those proposals to an increased risk of terrorism.

On Friday afternoon, Cruz took a swipe at Rubio for supporting an immigration overhaul in 2013. “If you’re supporting amnesty, you’re supporting the Obama-Clinton weakness and appeasement to radical Islamic terrorism,” he said in Orlando while rolling out an immigration policy blueprint.

Sen. Rand Paul also went after Rubio on Saturday during a speech in the Floridian’s home state for blocking an amendment Paul offered to the 2013 immigration bill which would have imposed higher scrutiny for people coming to the United States. “I think that was a mistake, not only for the bill, but also for national security,” Paul said of Rubio’s opposition, according to CNN. Rubio retorted Sunday on ABC: “Rand just uses this sort of rhetoric to distract from his very weak record on national security issues.”

At a rally Saturday in Beaumont, Texas, Trump called it “insane” for the U.S. to bring in Syrian refugees. He also deployed trademark bravado against a rival, saying Rubio “wants to give everybody amnesty.” He also claimed the Paris massacres may not have been so bad if the country had looser gun control laws.

Mike Huckabee, a marginal candidate in the GOP race, called for closing U.S. borders and imposing an immediate moratorium to keep out people from countries where “there is strong presence of ISIS or al-Qaida.”

It’s unclear how long the issue will reverberate in the primary, let alone how it will resonate in the general election debate. International affairs tend not to be a central consideration for Americans — just 8 percent of American voters said “foreign policy and the Middle East” was their top issue in an NBC/Wall Street Journal poll taken late October, although the number has been higher among Republicans.

In the near future, the attacks will prompt Republican primary voters to consider whether they truly want an outsider handling foreign policy and nuclear weapons, or whether they ultimately want someone with experience in government to be in charge of their security. The candidates are continuing to draw contrasts with President Barack Obama’s policies and Democratic front-runner Hillary Clinton’s view, expressed Saturday night during a debate, that “this cannot be an American fight, although American leadership is essential” in the battle against the Islamic State.

“Before a major national security event like this, voters reconcile their support for a candidate like Trump by arguing they want something different,” Madden said. “But, after an event like this the idea of a Trump candidacy could give them great pause.”

Photo: Republican U.S. presidential candidates (L-R) U.S. Senator Marco Rubio, businessman Donald Trump and Dr. Ben Carson pose before the start of the 2016 U.S. Republican presidential candidates debate held by CNBC in Boulder, Colorado, October 28, 2015. (REUTERS/Rick Wilking)