A glaring contrast on Iran among Clinton, Trump and Cruz

On Wednesday morning in Washington, a hoarse Hillary Clinton delivered a poised and methodical explanation of her decision to support the Iran nuclear deal inside the staid and climate-controlled confines of the buttoned-up Brookings Institution.

Three miles away and three hours later, under a baking sun on the west lawn of the U.S. Capitol, Sen. Ted Cruz of Texas and Donald Trump stood on a stage and railed against the same accord using apocalyptic language and stirring the emotions of a pugilistic tea party crowd that still detests Republican leadership as much as it does President Barack Obama.

The gap between the trio of 2016 presidential contenders on the most contentious foreign policy issue since the 2003 decision to invade Iraq was vast, not only in their positions, but in their presentations, provocations and knowledge of the topic.

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Clinton, while supportive, recognized the skepticism of the deal's opponents, answered their concerns head-on with detailed responses in her speech and emphasized what she posited would be her ruthless enforcement of the agreement. She also blasted Republicans for their "unserious" critiques of the deal negotiated with a half dozen other world powers.

"Several Republican candidates boast that 'I'll tear up this agreement in 2017', more than a year after it's been implemented. That's not leadership. That's recklessness," said the former secretary of state.

Trump made unrealistic promises -- like guaranteeing the return of four American hostages in Iran before he even takes office -- and then returned to his typical stump speech of colorful insults and lamenting America's dire position in the world.

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"All of these countries are going to do business with Iran, they're going to make lots of money and lots of other things with Iran and we're going to do and we're going to get nothing," he said. "We're led by very, very stupid people."

See more of Trump on the campaign trail:

Cruz's speech was tightly constructed, comprehensive and touched on more of the minutiae than Trump -- for instance, he named all four of the American prisoners and argued Senate Majority Leader Mitch McConnell and House Speaker John Boehner still had the legal authority to halt its implementation -- but his outline of the consequences of the deal were even more harrowing than Trump's. He questioned whether Democrats supporting it valued the safety and security of the United States and said any credible candidate for president should pledge to tear the deal up on his or her first day in office, a move Trump has even resisted.

"If you vote to send billions of dollars to jihadists who have pledged to murder Americans, then you bear direct responsibility for the murders carried out with the dollars you have given," Cruz said to cheers. "You cannot wash your hands of that blood."

While a Pew poll indicates just a fifth of the country supports the nuclear agreement with Iran, even more -- 30 percent -- have no opinion at all, an indication that the issue holds more resonance with party elites and foreign policy wonks in the northeast corridor than average voters in the heartland.

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Clinton's address was most important because it displayed her readiness to be commander-in-chief. She framed the deal not as a triumphant victory but rather as the best of undesirable options with a brutal state sponsor of terrorism. Iran was racing toward nuclear capacity; this will erect roadblocks to that capability for more 15 years and hand America more leverage if Iran cheats, Clinton argued.

"My starting point will be one of distrust. My approach will be distrust and verify," she said, adjusting President Ronald Reagan's famous phrase in dealing with the Soviet Union.

In a vivid display of her nuance and precision, she conceded that one provision that could leave the international community without access to some of Iran's nuclear facilities for up to 24 days was troubling.

"I'd be the first to say that this part of the deal is not perfect," Clinton said.

But she noted that even delayed inspections are better than no inspections since experts say microscopic nuclear particles are detectable for years.

She spent the second half of her remarks professing her unfettered allegiance to Israel, promising to arm the U.S. ally with some of the nation's most sophisticated airpower, the F-35, as well as the strongest air defense system. She'd roll out the carpet at the White House for the Israeli Prime Minister in the first month of her presidency.

See more of Clinton on the campaign trail:

Even in support of this Iran deal, Clinton's hawkish wings were apparent.

"I will not hesitate to take military action if Iran attempts to obtain a nuclear weapon," she said. "We will act decisively if we need to."

The atmosphere in the shadow of the Capitol dome was far less subtle.

A litany of comparisons were apocalyptic: Of Iran's leadership to Hitler, of Obama to the appeasement of Neville Chamberlain, of the prospect of a nuclear attack on American soil that would dwarf the Sept. 11 attacks in terms of casualties.

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An elderly woman held a sign that read: "Potus in bed with those who behead." Another man's blared: "Impeach Hussein Obama, Prosecute Hillary."

Cruz fed on these fears by saying that with this deal, the Obama administration would become the world's leading financier of Islamic terrorism. He didn't leave it to the crowd's imagination.

"If this deal goes through, we know to an absolute certainty people will die," Cruz declared. "Osama bin Laden never had $100 billion."

The crowd, which booed the names of McConnell and Boehner with more fervor than Obama, ate it up. Which explains why this crowd seemed even more receptive to Cruz than Trump, who looked to be there more to soak up the raucous audience than to dive into specifics on Iran.

Clinton has endured a fair amount of turbulence as a candidate in recent weeks. But on this day, she benefited from a contrast on foreign policy with both Cruz and Trump.

They attracted the crowd and cheers in a carnival-like atmosphere; she looked like someone who knows her way around the world and the White House.

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