The open letter to the leaders of the Islamic Republic of Iran signed by 47 senators and instigated by Sen. Tom Cotton (R-Ark.) was a stunning breach of protocol. One so outrageous that my former colleagues at the New York Daily News dubbed the signers “traitors.” While it is indeed a slap in the face of President Obama and an affront to the presidency, I’m not sure I would go that far, especially since Cotton is an Army veteran of the Iraq and Afghanistan wars. So, I turned to retired Major Gen. Paul D. Eaton for perspective. He wouldn’t say Cotton and Co. were “traitors,” either. He had a better word.

“I would use the word mutinous,” said Eaton, whose long career includes training Iraqi forces from 2003 to 2004. He is now a senior adviser to VoteVets.org. “I do not believe these senators were trying to sell out America. I do believe they defied the chain of command in what could be construed as an illegal act.” Eaton certainly had stern words for Cotton.

“What Senator Cotton did is a gross breach of discipline, and especially as a veteran of the Army, he should know better,” Eaton told me. “I have no issue with Senator Cotton, or others, voicing their opinion in opposition to any deal to halt Iran’s nuclear progress. Speaking out on these issues is clearly part of his job. But to directly engage a foreign entity, in this way, undermining the strategy and work of our diplomats and our Commander in Chief, strains the very discipline and structure that our foreign relations depend on, to succeed.” The consequences of Cotton’s missive were plainly apparent to Eaton. “The breach of discipline is extremely dangerous, because undermining our diplomatic efforts, at this moment, brings us another step closer to a very costly and perilous war with Iran,” he said.

“I think Senator Cotton recognizes this, and he simply does not care,” Eaton went on to say. “That’s what disappoints me the most.” And that’s what’s so scary about this whole episode. The freshman senator from Arkansas and 46 of his Republican colleagues sought to bigfoot Obama on a deal not yet done whose details are not yet known.

In his column today, Michael Gerson makes a point that should have been obvious to all the signatories of the Cotton letter.

If Republican senators want to make the point that an Iran deal requires a treaty, they should make that case to the American people, not to the Iranians. Congress simply has no business conducting foreign policy with a foreign government, especially an adversarial one. Every Republican who pictures his or her feet up on the Resolute Desk should fear this precedent.

This is a point you imagine Sen. John McCain (R-Ariz.) would have made back in the good old days when he was a statesman. Instead, he signed the letter.

“I expect better from the men and women who wore the uniform,” Eaton said of Cotton. And the American people deserve better from the Senate.

Follow Jonathan on Twitter: @Capehartj

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