U.S. Secretary of State John Kerry, left, listens to Iran's Foreign Minister Mohammad Javad Zarif, right, before resuming talks over Iran's nuclear program in Lausanne, Switzerland, Monday, March 16, 2015. (Brian Snyder/AP)

It is the common temptation of Republicans and Democrats to support a strong presidency when it is used to do things they like and to condemn it when it does things they don’t. There is, however, a group of committed institutionalists that has gathered around the bipartisan Iran Nuclear Agreement Review Act, now scheduled for a vote of the Senate Foreign Relations Committee on April 14.

The bill is carefully limited in scope, setting a 60-day review period following a nuclear agreement in which Congress can waive (or not) the congressionally mandated sanctions against Iran. Policy related to United Nations sanctions and executive-imposed sanctions would be left entirely to the president. The administration concedes that Congress should eventually have a role in determining the shape of congressional sanctions; the legislation would merely move a congressional vote from the end of the process to the beginning.

President Obama has promised to veto the measure. His intention (assuming an agreement with Iran is reached) is to waive congressional sanctions until after his time in office ends.

Senate proponents of the Review Act count 11 Democratic supporters, including institutionalists such as Sen. Tim Kaine of Virginia. Assuming all Republican senators come along, only two more Democrats are necessary for a veto-proof majority. The effort to secure those votes was set back by Sen. Tom Cotton’s (R-Ark.) ill-advised, partisan “Dear Mullah” letter. In the estimate of one supporter of the Review Act, six or seven Democratic senators went from gettable to ungettable. The committee vote was delayed until mid-April, in part to allow partisan tempers to cool.

Many Republican senators are open to supporting a reasonable nuclear deal with Iran. But they have a series of reasonable concerns. Several weeks ago, the multilateral negotiating process — including the five members of the U.N. Security Council, plus Germany — was effectively superseded when the Obama administration began direct talks with the Iranians. Since then, one senator told me on background, the United States has moved “every day closer to the Iranian position.” This is the source of increasingly vocal concern from excluded partners — including the French, who called for a stiffened spine in negotiations.

As with any nuclear agreement, the devil — or, in this case, the Great Satan — is in the details. What kinds of centrifuges should be allowed? What sort of inspections would limit the prospect of Iranian covert actions? What do we need to know about the previous military dimensions of the Iranian nuclear program? (Recent talks have raised the prospect that Iranian Foreign Minister Mohammad Javad Zarif may not fully know what the Iranian Revolutionary Guard Corps has been doing.)

Senate Republicans not only fear a bad deal, they sense a major shift in American policy — a desire to cozy up with Iran in the fight against Sunni extremism. Such a regional rebalancing would involve a shift away from Israel and America’s traditional Arab partners. (This prospect — and not a personality clash between Obama and Prime Minister Benjamin Netanyahu — is the main source of Israeli angst.) The result can already be seen in Iraq, where Iranian allies have permeated the parliament and where Maj. Gen. Qasem Soleimani, the Revolutionary Guard’s Quds Force commander, has become a folk hero among Iraqi Shiites.

Evidence for an evolving administration attitude toward Iran has been on recent display. Recently, Syrian dictator Bashar al-Assad has dropped “barrel bombs” filled with chlorine gas on civilians — crossing yet another American “red line.” But punishing the Assad regime with anything more than a tongue-lashing would offend its Iranian sponsor and, perhaps, disrupt nuclear negotiations. So: Assad commits crimes against humanity, while Obama is really angry about Netanyahu’s campaign strategy.

America’s strategic shift in the Middle East is leaving deep, unresolved contradictions. The United States is vetting, training and equipping moderate rebels to enter Syria, who will be promptly barrel-bombed by the Assad regime, which America has no intention of preventing. (Defense Secretary Ash Carter and Gen. Martin Dempsey, the chairman of the Joint Chiefs of Staff, recently testified that they have no authority to protect American-trained proxies in Syria.) It is a policy so impractical, so careless of consequences, that it is immoral.

The administration is attempting a series of enormously complex, consequential diplomatic maneuvers — for which it has shown no aptitude in the past (see the Russian “reset” and three years of disastrous Syrian inaction). But members of Congress are being told to sit down and shut up. Stunts such as the Cotton letter are counterproductive. Responses such as the Review Act are badly needed.

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