WASHINGTON – While other Republican presidential candidates are taking swipes at front-runner Donald Trump, Sen. Ted Cruz, R-Texas, is instead joining forces with him to try to stop President Obama's nuclear deal with Iran.

Cruz invited Trump to join a Capitol Hill rally and Trump accepted, telling people at an event in South Carolina, it will be "essentially a protest against a totally incompetent deal we're making with Iran."

Cruz tweeted that he was glad Trump had accepted the invitation.

A statement from Catherine Frazier, national press secretary for the Cruz presidential campaign, said:

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"Sen. Cruz has invited Donald Trump to join him on the Capitol grounds for a rally to call on members of Congress to defeat the catastrophic deal that the Obama administration has struck with the Islamic Republic of Iran. The event will be sponsored by Tea Party Patriots, Center for Security Policy, and the Zionist Organization of America. We are thankful for all their hard work on this effort and will have more details on time, date, and location as they are finalized."

The Tea Party Patriots have since announced the rally will be on Wednesday, Sept. 9, on the West Lawn of the Capitol.

"This deal does not prevent Iran from getting nuclear weapons; it virtually guarantees it. Congress must reject this terrible deal," said Jenny Beth Martin, the CEO and co-founder of Tea Party Patriots.

While some of the other GOP candidates, notably Jeb Bush, have attacked Trump and become ensnared in a war of words, Cruz has refrained. The senator has said he agrees with Trump on many key issues.

Trump joked Thursday he wouldn't "hit" Cruz who has been "so nice." But Trump kiddingly added, "I may have to if he starts getting really close."

Cruz and Trump met earlier this summer in New York but did not reveal what they discussed.

Obama's Iran deal has been blasted by critics as dangerously unrealistic.

Even top Democrats have come out against it.

Sens. Chuck Schumer, D-N.Y., and Bob Menendez, D-N.J., both plan to vote for an upcoming Senate bill disapproving of the deal.

J.B. Pritzker, a lifelong Democrat who chaired Hillary's 2008 campaign, wrote last week:

"Regrettably, the Iran deal fails to meet these goals and raises the prospects for war ... By legitimizing Iran’s nuclear program, removing the pressure of economic sanctions and allowing it to obtain conventional weapons and ballistic missiles, this agreement makes the prospect for war more likely, not less."

President Bill Clinton's CIA director, James Woolsey, also wrote last week:

"Congress must stop President Obama’s nuclear deal with Iran. The most important reason — Iran can threaten the existence of the United States by making an electromagnetic pulse (EMP) attack using a single nuclear weapon."

WND has worked extensively with one of the groups sponsoring the anti-Iran deal rally, the Center for Security Policy.

Clare Lopez, the group's vice president, is one of the top experts on Iran.

She told WND the Cruz and Trump rally is "a great development, because these two are among the sharpest, best-informed of the entire candidate lineup," and that the duo "speak out forthrightly about what they believe."

"To see them taking a public stance against this disaster of a deal is important and encouraging," concluded Lopez.

Earlier this week, she told WND she concurred with the detailed assessment recently published by John Bolton, the former U.S. ambassador to the U.N., that only a military strike can now stop Iran’s nuclear weapons program.

And Lopez told WND she agreed that such a strike "does not necessarily mean all-out war."

While she also agreed with Bolton that stopping President Obama's nuclear deal will not prevent Iran from getting the bomb, Lopez still stressed the importance of having Congress reject the agreement.

She insisted it's worth voting down the deal as an expression of the will of the American people and their recognition that it is a bad deal, and because there seems to be some indication that Iranian Supreme Leader Ali Khamenei will make his own decision, up or down, based on the vote in Congress.

"As Iranian experts have explained to me, and as (Iran expert and former Harvard professor) Daniel Pipes has also written, there is strong opposition to this deal inside the Iranian regime itself. And the embarrassment before the world should Congress indeed vote it down would be unbearable to the supreme leader," said Lopez.

She said that means Khamenei "cannot get out in front. Nor is the Majlis (the Iranian parliament) likely to vote on it before Congress. This makes Congress's vote even more important than many may realize."

Lopez was an instructor for military intelligence and special forces students; has been a consultant, intelligence analyst and researcher within the defense sector; has published two books on Iran; and has an analytical acumen honed by 20 years as a CIA field operative.

She appeared as a speaker at a "Stop Iran Rally" recently in Cleveland and another rally in Santa Barbara, California, on Sunday.

"Absolutely insane," was the succinct reaction from Lopez to WND on the revelations last week of details in the secret side deals in Obama's nuclear agreement with Iran.

The Associated Press had confirmed a pair of stunning details in the agreement:

A secret side deal lets Iran decide which sites to inspect.

The side deal also lets Iran do the inspections at a key site.

AP reported it had reviewed a document outlining the side deal between Iran and the International Atomic Energy Agency, or IAEA.

In a nutshell, the secret side deal would:

Let Iran use its own inspectors to investigate the Parchin site where experts suspect it has been developing nuclear arms.

Let Iran provide the IAEA its own photos and and videos of suspect locations, while, "taking into account military concerns."

AP said that wording suggests international inspectors will be barred from sites Iran declares have "military concerns."

AP said the wording also suggests the IAEA won't get photo or video information from areas Iran says are off limits because they have military significance.

While the document says the IAEA "will ensure the technical authenticity" of Iran's inspection, it does not say how.

"Never before did the IAEA simply allow a party suspected of violations to inspect themselves," a stunned Lopez told WND.

There is apparently more than one side deal.

AP reported the document is labeled "separate arrangement II," which indicates there is at least one more confidential agreement between the IAEA and Iran.

AP said the document it reviewed is a draft, but "one official familiar with its contents said it doesn't differ substantially from the final version."

The IAEA chief told Republican senators two weeks ago that he could not let them see the side deal.

“Enough," responded Cruz.

"Enough of the concessions, capitulations and backroom deals that make up President Obama’s catastrophic nuclear deal with the Islamic Republic of Iran. The most recent revelation that Iran will be selecting its own inspectors to verify the nature of its nuclear program is made all the more egregious by the fact that as the single largest contributor to the IAEA (support that is mandated in the deal) United States taxpayers will be paying for a farce that is a direct threat to their own security."

Cruz concluded, "This is not a partisan issue. It is not about President Obama’s political legacy. It is about the future of our country, and that of our allies. We have to stop this disastrous deal."

Lopez rhetorically asked WND: "Why do inspections at all at sites deemed 'suspect' if those suspected of doing something that violates the deal are going to be trusted, essentially, with inspecting themselves?

"Was there ever anything more absurd?" she wondered incredulously.

"That's not how the IAEA inspects any other country with a nuclear program. When (former Libyan leader Moammar) Gadhafi gave up his weapons of mass destruction program, the various agency inspectors were given access everywhere to verify that he'd genuinely given up.

"When South Africa terminated its nuclear weapons program under IAEA supervision, the government welcomed the inspectors and gave them access to wherever they needed to go. It's attitude was one of cooperation and transparency. That's not how Saddam Hussein behaved, and it's not how Iran's regime is behaving now," she concluded.

Critics of the Iran deal say it is based on trust of the Iranian regime while the administration claimed on Wednesday "the IAEA has separately developed the most robust inspection regime ever peacefully negotiated."

AP reported, "The agreement in question diverges from normal procedures by allowing Tehran to employ its own experts and equipment in the search for evidence of activities it has consistently denied – trying to develop nuclear weapons."

The deputy IAEA director general in charge of the Iran probe from 2005 to 2010 told AP he could think of no similar concession with any other country.

Secretary of State John Kerry said in April that, under the deal, Iran would allow the IAEA to inspect anywhere it wants. He would later deny saying that, while testifying under oath to Congress.

After the deal was concluded, Kerry told senators on July 23 he "never uttered the words anywhere, anytime" regarding inspections of Iran’s facilities, and claimed "it was never part of negotiations."

That’s not what the Obama administration said in April, and it directly contradicted what Deputy National Security adviser Ben Rhodes promised back then, when he said the International Atomic Energy Agency would have immediate access to any Iranian nuclear site.

Rhodes has since flip-flopped and directly contradicted himself.

On April 6, he said, "Under this deal, you will have anywhere, anytime, 24/7 access as it relates to the nuclear facilities that Iran has."

On July 14, he said, "We never sought in this negotiation the capacity for so-called anytime, anywhere" inspections.

Parchin is just one of the sites where Iran has not permitted IAEA inspectors to go.

Iran has denied any nuclear weapons work was done at Parchin but has never allowed access to the site. The IEAE suspects Iran experimented on nuclear detonators at Parchin, based on U.S., Israeli and other intelligence.

Work at Parchin stopped more than decade ago, but the IAEA has cited satellite image evidence of apparent attempts to clean the site.

Lopez told WND in April that if "you read between the lines" of its report back in November 2011, it was clear that even the IAEA believed Iran had been working on a nuclear warhead as well as the explosive triggers for initiating the implosion sequence.

She also said, "All the evidence suggests Iran already has nuclear warheads."

Worse yet, she said the Obama administration almost certainly knows that.

"IAEA (International Atomic Energy Agency) reporting over recent years indicates at a minimum they strongly suspect that Iran already has built nuclear warheads. It's certainly known that Iran has long range ICBMs (intercontinental ballistic missiles.)"

Lopez added, "They've had the information how to build a warhead for a long time. They've had expert assistance from, at a minimum, North Korea and Pakistan."

"They're documented by the IAEA as having engaged in activities related to warhead development. There are satellite images from Parchin of what are believed to be 'containers' in which warhead triggers were tested. And Iranian officials have been reported present in North Korea during nuclear tests."

Follow Garth Kant @DCgarth

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