Washington DC - The attacks in Paris have once more put foreign policy and immigration at the centre of the Republican presidential campaign, opening up a clear divide with the Democrats and allowing those chasing the nomination to hammer Hillary Clinton and the Obama administration.
It is too early to suggest, as some commentators have, that this will be the defining issue next November. However, it will highlight national security.
It's no longer about Osama bin Laden. It's now all about the Islamic State of Iraq and the Levant (ISIL) group and whether the US gets pulled deeper into a conflict in a region it's been desperate to leave behind.
Some of those running for the nomination are governors. And they have joined the growing chorus of voices insisting their states will not accept refugees from Syria.
Whether or not they can legally prevent it, however, is murky.
The power of entry to the country is with the federal government - once in the US, everyone, including refugees, are allowed freedom of movement. No state is going to set up its own border controls, while refusing entry would bring an immediate lawsuit.
All the Republican hopefuls have spoken out about Paris. Grasping the opportunity to talk foreign policy - a key part of the president's job - they've expressed their concerns about the attacks and their solidarity with France.
Donald Trump has been talking for days about "bombing the sh##" out of ISIL. It's a line which brings big cheers and resonates with many of supporters who want someone who will not only understand their fears, but will actually do something about them.
And that sort of rhetoric might appeal to others too.
In a recent Reuters poll among Republican voters, 41 percent backed Trump as their favourite candidate to handle foreign policy, while 39 percent picked Ben Carson - neither Trump, nor Carson, have any real experience in the wider international area.
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In an interview on Monday, Trump suggested that if he was president, he might shut down some mosques.
"I would hate to do it, but it's something you're going to have to strongly consider, because some of the ideas and some of the hatred is coming from these areas," he told MSNBC.
And on the idea of allowing more refugees, he suggested it could be a "Trojan horse".
"We have no idea who these people are, we are the worst when it comes to paperwork," he said.
Refugee plan attacked
The Obama administration has admitted just slightly more than 1,600 Syrian refugees over the past year and wants to provide a haven for up to 10,000 more in the coming 12 months.
[To allow Syrian refugees to settle in the US] would be the height of foolishness to bring in tens of thousands of people including jihadists that are coming here to murder innocent Americans.
Yet, the other Republican frontrunner, retired neurosurgeon Ben Carson believes this also provides cover for potential attacks in the US: "If I were one of the leaders of the global jihadist movement and I didn't infiltrate that group of people with my people, that would be almost malpractice."
On Friday, just hours after the attacks, Texas Senator Ted Cruz attacked the immigration plan.
He has previously criticised President Obama for refusing to use the term "radical Islamic terrorism" and he insisted following through on the plan to allow Syrian refugees to settle in the US "would be the height of foolishness to bring in tens of thousands of people including jihadists that are coming here to murder innocent Americans".
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Along with Jeb Bush, he has suggested there should be no such ban on Christian refugees. The former Florida governor called for safe havens in Syria as an alternative to relocating people in the US.
"There is a special important need to make sure that Christians from Syria are being protected because they are being slaughtered in the country," he added.
Such an idea has been sharply criticised by Obama.
Speaking at the G20 summit in Turkey, he said: "That's shameful. That's not American. That's not who we are. We don't have religious tests to our compassion."
Kentucky Senator Rand Paul has said that he plans to introduce legislation which will put a halt to visas for refugees from 30 countries that have "significant jihadist movements".
He said the cost of the legislation will be covered by a special tax on arm sales to any of those countries.
Paul also took the opportunity to attack rival Florida Senator Marco Rubio for opposing an amendment he had put into the 2013 Immigration bill which would have increased screenings for anyone entering the country.
"I think that was a mistake not only for the bill, but also for our national security," he said.
'Not even three-year-old orphans'
Marco Rubio has a problem. And it's not just with Rand Paul.
In the last couple of days, he has said that the US "won't be able to take any more" refugees. But in September, he had said he was open to the "relocation of some of these individuals at some point in time to the United States".
This has led several prominent and influential right-wing websites to brand the senator as a "flip flopper" - often the kiss of death for a candidate. And that comes as he was beginning to make significant gains in the polls.
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Former Arkansas Governor Mike Huckabee has added his voice to the demands for Syrian refugees to be turned away, saying: "It's time to wake up and smell the falafel. We are importing terrorism."
Businesswoman Carly Fiorina had previously expressed her opposition to allowing refugees into the country - and did so again after the events in Paris.
She said Obama was wrong when he insisted that ISIL was being contained: "Mr President, they are not contained, they are at our shores and they measure their victory in body count."
Senator Lindsay Graham, who has called in the past for the country to take its fair share of refugees and has called for US troops on the ground in Syria to take the fight to ISIL, has perhaps realised that part of his argument would not be a vote winner with Republicans in the current climate.
He told a right-wing radio station: "The one thing I've learned from Paris is that we need to have a time-out on bringing refugees into this country until we have a system that we think will work."
Candidates Rick Santorum and George Pataki want the refugee programme halted. "Obama looked the other way" on ISIL, said Pataki.
Current governors John Kasich, Bobby Jindal and Chris Christie insisted their states would join the others in refusing the settle refugees - "not even three-year-old orphans", said Christie.
While the rhetoric is hot and candidates seemingly united, the response also poses a serious question for the voters.
Do they stick with the outsiders, who are strong on sentiment but short on international experience? Or do they seek someone with government experience to handle the next stage of the fight against ISIL?
Their attitudes and answers will change this race.
Source: Al Jazeera