Second GOP debate to feature foreign policy test

If there's an "oops" moment under the klieg lights this year, Wednesday night could be when it transpires.

But the Republican candidates heading into their second presidential primary debate can't say they haven't been warned.

Hugh Hewitt – the widely respected conservative radio talk show host – will assist CNN in the evening's questioning and has already promised to toss tough queries about security and defense at the 11 candidates in the main showdown.

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He's already tripped up the two current GOP front-runners. Donald Trump told Hewitt earlier this month he couldn't identify the names of the leaders of major terrorist groups and confused a question about the Quds force – an elite Iranian military unit – as being about the Kurds, an ethnic group and U.S. ally in northern Iraq. In March, it was Ben Carson who faltered at the hands of Hewitt, misstating that the Baltic states weren't part of NATO.

On Wednesday night at the Ronald Reagan Presidential Library, the two will stand center stage, which means they will likely command the most attention. But the rest of the fleet will also have opportunities to shine or shrivel when cross-examined about their qualifications to be commander-in-chief.

Click through for images of the first GOP debate:

"Everyone's already showed they know what's wrong with [President Barack] Obama's foreign policy. But at this debate, they're going to have to get beyond complaining about leading from behind and saying they'll make America great again," says Kori Schake, a research fellow at the Hoover Institution whom Hewitt has consulted with to formulate debate questions. "Everyone eventually has to answer that Hillary Clinton 3 a.m. phone call."

There's widespread consensus among the Republican slate when it comes to the broad strokes of foreign policy: The Islamic State group must be eradicated. The Iran nuclear deal should be nullified. Military spending ought to rise.

But look for the wonkish Hewitt to try and pin the pack down on specifics and press them to flesh out exactly how they'd accomplish what they're proposing.

SEE MORE DEBATE COVERAGE AT AOL.COM

A possible example: A central tenet of the Iranian nuclear deal is the loosening of international economic sanctions that are stifling the country. If the agreement could be trashed in 2017, how would a Republican president force the Europeans and Russians to reimpose those sanctions?

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Another: How does a GOP president accomplish the dual – but conflicting – goals of lifting military spending and reducing the $18 trillion national debt?

"It's not clear to me, as a conservative, those two plans add up," Schake says.

One topic almost certain to arise is defining the U.S. role in the Syrian refugee crisis. On this humanitarian catastrophe, there are discernible divides between the candidates on whether to accept an influx of foreigners fleeing their country due to sustained violence.

Trump last week became an odd bedfellow with Sen. Lindsey Graham, R-S.C., when he said the U.S. has to allow some Syrian refugees into the country. Jeb Bush and Sen. Marco Rubio, R-Fla., also have offered cautious support for a plan to accept Middle Eastern refugees, whereas Sen. Ted Cruz, R-Texas, said such a move doesn't "make sense." Wisconsin Gov. Scott Walker has taken one of the hardest lines against refugees, arguing that the real focus should be on the Islamic State group, whose reign of terror is among the things causing them to flee.

RELATED: A Glaring Contrast On Iran Among Clinton, Trump and Cruz

Appearing Sunday on ABC's "This Week", Carson wasn't clear either way, but appeared to oppose permitting refugees to seek safe haven in America, saying doing so "carries extra danger."

The 63-year-old retired neurosurgeon, now second to Trump in almost every primary poll, has thus far relied heavily on medical analogies and his brainpower to deflect questions about his readiness to navigate the globe's most roiling predicaments.

"The thing that's probably most important is having a brain and to be able to figure things out and learn things very rapidly," Carson said during the first debate, prompting audience cheers.

See more of Carson on the campaign trail:

The only military adviser to Carson his campaign will name is retired Army Gen. Bob Dees, but a spokesman tells U.S. News the candidate has devoted more time to studying foreign policy in the run-up to this debate and will make public more advisers later this year.

Schake says Carson "definitely will have to show" more depth and breadth on foreign policy.

"'I'll ask smart people and use good judgment' is a good first-order answer," she says. "But it doesn't answer, 'What would you do now in Syria?'"

Trump similarly has foregone outlining a sweeping and detailed foreign policy vision, revealing he takes his advisement from newspapers and generals appearing on television. He's also said he'll skip overseas trips during the primary – a common tactic of serious candidates – to keep his focus trained on the problems at home.

Asked if Trump and Carson have proved themselves ready to be commander-in-chief, former U.S. Sen. Jim Talent, R-Mo., says "that's a question still to be decided."

"I don't think either one of them has talked in-depth about what they want to do in foreign policy," says Talent, who's now coaching Walker on international issues.

Tom Ridge, the former Pennsylvania governor who served as the nation's first secretary of homeland security, thinks Bush has an opportunity to stand out on foreign affairs by exhibiting calm and competency, and by being resolute.

But Bush's rivals have tried to use his placid demeanor against him. Trump has hazed Bush for being "low-energy," while Walker has taken a shot at him for refusing to say he'd shred the Iranian agreement on his first day in office.

"Unlike others, I don't need months or years to mull this over," Walker said in a speech at The Citadel in South Carolina. "I will terminate it on Day One."

Ridge, who has advised Bush on national security, says that remark shows Walker's naiveté.

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"I like Scott Walker, but that's red meat, that means nothing. It sounds like, 'I'm gonna build a wall.' [The deal's] done. Tearing up the agreement, it's meaningless, it's rhetorical, it's absurd, it has no effect on how you deal with Iran long-term," Ridge says. "We're not going to be able to impose the sanctions again. No serious person would believe that."

Mike Rogers, a former chairman of the House Intelligence Committee who's now holding a host of national security forums across the country, also viewed Walker's rhetoric as unrealistic and thinks Bush has displayed a more responsible approach to Iran.

"One of the best answers I've heard was from Jeb Bush, who said he would ask Europeans to re-engage on sanctions and lay out the gauntlet that he would be willing to deny Iran's access to the reinsurance market in the U.S. and access to our financial institutions, which is huge. To me, that is a walk-that-thing-back approach versus 'rip it up,'" Rogers says. "You have to be able to promote a message of firmness without reactionary rhetoric."

But Walker's harder line juxtaposed with Bush's more methodical approach provides a temperamental contrast for voters to appraise.

"He's a decisive person," Talent says of Walker. "His decision that we should have canceled the Chinese [president's] visit [this month] was bold and correct."

See more of Walker on the campaign trail:

Rubio, another promising contender in need of a breakout moment, has bet much of his campaign on an aggressive foreign policy posture. He is arguably the most fluid speaker on the topic, but will be competing for attention with Cruz – who has invoked some of the most severe language in describing the Iran deal – and Ohio Gov. John Kasich, who served 18 years on the House Armed Services Committee and can highlight a portfolio of experience.

Carly Fiorina, who scrapped her way onto the main debate stage this time, has also proved fluent on worldwide hot spots, rattling off the names of world leaders she met globe-trotting as CEO of Hewlett-Packard. Her leadership of the CIA's External Advisory Board at the end of President George W. Bush's administration is a lesser-known part of her biography, but her command of the topic is quietly grabbing the attention of the party's foreign policy establishment.

"She sort of surprised me just because I thought she was a corporate person," Rogers says. "I've been very impressed with her grasp and understanding on things you need to show resolution on, and still understanding the nuance of national security."

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