So let’s get this straight: Iranian-backed rebels have overthrown the pro-American government in Yemen that was helping us fight al-Qaeda’s most dangerous branch. The Iranian Revolutionary Guard has deployed its terrorist Quds Force into Iraq, and its infamous commander, Gen. Qasem Soleimani, is on the ground leading the offensive against the Islamic State. Iran is on the verge of getting the world to lift economic sanctions in exchange for a nuclear agreement so bad that it has actually united Arabs and Israelis in opposition.

And Washington is concerned with . . . protocol.

It was a violation of protocol, we are told, for House Speaker John Boehner to invite Israeli Prime Minister Benjamin Netanyahu to explain the dangers of the Iran accord to Congress. It was a violation of protocol for Sen. Tom Cotton (R-Ark.) and 46 other Republican senators to issue an open letter to Iran’s leaders explaining that any agreement they reach with Obama might not survive his presidency.

To hell with protocol. Iran is on the march across the Middle East. The regime in Tehran is turning Iraq (a country thousands of Americas died to liberate) into an Iranian proto-satellite state. It is propping up the murderous regime of Bashar al-Assad in Syria that has killed some 200,000 people. It is using proxies such as Hamas, Hezbollah and the Houthis in Yemen to conduct jihad against the West. And President Obama is trying to turn Iran into a partner in peace — promising that if Iran cooperates with the United States, it could become “a very successful regional power.”

Iran already is “a very successful regional power.” And it believes it could become even more successful if it had a nuclear weapon.

Secretary of State John Kerry and his Iranian counterpart, Mohammad Javad Zarif, resume nuclear talks Switzerland before a March 31 deadline for a political agreement. (Reuters)

The Obama administration is negotiating an accord that would bring Iran closer to that objective. The agreement Obama is negotiating would reportedly lift sanctions on Iran without requiring the regime to dismantle a single element of its nuclear program or cease its development of intercontinental ballistic missiles. This means that when the accord expires in a decade (another disastrous concession) Iran could then break out as a nuclear power with missiles that can deliver mass destruction far beyond the Middle East. The result could be a nuclear arms race in the Middle East, as the United States’ Gulf allies race to develop a nuclear deterrent of their own to counter a nuclear Iran. And a nuclear Iran would be even more emboldened to destabilize its neighbors and seek to impose its hegemony across the region.

So let’s be clear: With all due respect to Miss Manners, protocol breaches are the least of our problems. To the contrary, we should be thankful there are still leaders in Washington like Cotton who are willing to throw their bodies on the tracks to stop the runaway train of Obama’s failed Iran policy.

On Sunday, Secretary of State John Kerry declared Cotton’s open letter to Iranian leaders “unconstitutional.” Apparently Kerry is unfamiliar with a part of that document called the First Amendment. And perhaps Kerry — and all those who are complaining about protocol and constitutional violations — could answer a simple question: Would it be a violation of protocol for the Obama administration to seek the United Nations’ approval of its Iran deal while circumventing Congress? Where in the Constitution does it say that the president can get the U.N. Security Council to make an agreement legally binding on our country without the approval of the elected representatives of the American people?

Apparently the Obama administration is contemplating doing just that — using a Security Council vote on its Iran deal to impose an international legal obligation on the United States, in an effort to prevent the next president from withdrawing from the agreement and reimposing sanctions. Of course, Obama cannot, in fact, use the U.N. to bind the next president. The Constitution trumps the U.N. Charter. Congress must pass legislation implementing Security Council resolutions for them to carry force of law, and it is unlikely Congress would ever do so in this case. But the fact that the Obama administration would even consider such an end run around Congress, while accusing its Republican critics of violating the Constitution, is sheer hypocrisy. And untold damage to our nation’s security will be done, since once the international sanctions regime is dismantled, it will be impossible to reimpose.

Cotton and his GOP colleagues have every right to publicly express their opposition to the Iran accord. And if a simple press release from 47 senators is enough to blow up Obama’s nuclear deal, then good for them. The republic will be safer as a result.

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Freshman Republican Sen. Tom Cotton told CBS News he stands behind his letter to Iran, saying it is critical to stopping them from getting a nuclear weapon. (Reuters)