In this Oct. 31, 2014 file photo, then-Rep., now Sen. Tom Cotton, R-Ark, speaks in Jonesboro, Ark. (Danny Johnston/AP)
Opinion writer

The true scandal of the Tom Cotton letter to Iranian leaders is the manner in which the Republican Senate apparently conducts its affairs.

The document was crafted by a senator with two months of experience under his belt. It was signed by some members rushing off the Senate floor to catch airplanes, often with little close analysis. Many of the 47 signatories reasoned that Senate Majority Leader Mitch McConnell’s endorsement was vetting enough. There was no caucus-wide debate about strategy; no consultation with Senate Foreign Relations Committee Chairman Bob Corker (R-Tenn.), who has studiously followed the nuclear talks (and who refused to sign).

This was a foreign policy maneuver, in the middle of a high-stakes negotiation, with all the gravity and deliberation of a blog posting. In timing, tone and substance, it raises questions about the Republican majority’s capacity to govern.

It is true that President Obama set this little drama in motion. Major arms-control treaties have traditionally involved advice and consent by the Senate. Obama is proposing to expand the practice of executive agreements to cover his prospective Iranian deal — effectively cutting senators out of the process. By renewing a long-standing balance-of-powers debate — in a way that highlights his propensity for power-grabbiness — Obama invited resistance. And there is a practical argument for Senate approval of arms-control agreements: It strengthens and empowers the president in punishing violations. The whole U.S. government is placed on record promising consequences for infractions (if, of course, the Senate concurs).

The exact shape of a possible Iran deal remains unknown. I’m on record predicting that it may be a bad one — a very unlikely throw of the dice that a terror-sponsoring, clerical regime will become a minimally responsible regional power.

Sen. Rand Paul (R-Ky.) said that the letter signed by 47 Republican senators to Iran was spurred by the Obama administration's actions. (AP)

But the half-baked Cotton letter was a poor instrument to express concern. First, the bleedingly obvious: 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.

In this particular situation, paradoxically, the main result is not a weakened presidency but a weakened legislature. Corker has been toiling with the ranking Democrat on the Foreign Relations Committee, Sen. Robert Menendez (N.J.), to craft legislation that would require Senate approval of an Iran deal. Before the Cotton letter, Corker was two votes away from a veto-proof, bipartisan majority. Now Obama and Minority Leader Harry Reid (D-Nev.) are using the letter to argue that Republicans are engaged only in partisan games. Peeling even a few Democrats off the Corker/Menendez approach could prove decisive. If the Corker bill fails narrowly, Obama might have Cotton’s missive to thank.

A final objection to the Cotton letter concerns not institutional positioning but grand strategy. The alternative to a bad nuclear deal is not war; it is strong sanctions and covert actions to limit Iranian capacities until the regime falls (as it came close to doing in 2009) or demonstrates behavior change in a variety of areas. But this approach depends on the tightening of sanctions in cooperation with Europe, as well as Russia and China. And this effort can be held together only by the impression that the United States has negotiated with Iran in good faith. So negotiations are actually an important part of any attempt to isolate Iran. The key is where we draw our “red lines.”

The Cotton letter creates the impression that Senate Republicans are rooting for negotiations to fail — which would complicate our attempt to maintain strong sanctions if negotiations end up failing.

In the aftermath of the letter, we are seeing the logic of partisan escalation. Didn’t Democrats open their own rogue negotiations with Nicaraguan dictator Daniel Ortega in the 1980s? Or sip tea with Syria’s Bashar al-Assad against the wishes of the George W. Bush administration? Of course they did. But justifying a bad idea by recounting a history of bad ideas is a particularly bad way to conduct foreign policy. It is the crutch of a partisan, not the argument of a statesman.

This is presumably the reason we have a Senate, not only a House. A six-year term should ensure an extra 30 minutes to read a document and think through its implications.

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