Now that the P5+1 and Iran have inked a deal that will unleash Tehran from decades of international sanctions, the agreement has to go before the legislatures in Iran and the US. The former is a mere formality; if Supreme Leader Ali Khameini likes the deal — and there’s zero reason to believe that Iranian negotiators would have acted without his express permission — then the Iranian parliament will rubber-stamp it. That leaves Congress as the last remaining stage on which this deal must play before full implementation. Bloomberg’s Billy House sees a rocky path ahead for the deal, but will it be rocky enough to halt it?

The U.S. Congress will begin its scrutiny of the international nuclear agreement with Iran amid heavy skepticism among Republicans, many of whom said in advance that they’re prepared to reject a deal that’s weak and gives too much leeway to Tehran.

Under legislation passed in May, Congress will have 60 days for public debate and hearings by as many as eight Senate and House committees. Lawmakers then could vote on a joint resolution to approve or reject the nuclear deal, though they also may not act at all.

The Iran deal is “going to be a hard sell” in Congress, Senate Majority Leader Mitch McConnell said on “Fox News Sunday.” He said President Barack Obama “knows that the resolution of disapproval is likely to be introduced, is very likely to pass and very likely to get over 60 votes.”

Of course he does. In his statement earlier today, Obama already announced that he would veto any measure of disapproval:

So I welcome a robust debate in Congress on this issue and I welcome scrutiny of the details of this agreement. But I will remind Congress that you don’t make deals like this with your friends. We negotiated arms control agreements with the Soviet Union when that nation was committed to our destruction and those agreements ultimately made us safer.

I am confident that this deal will meet the national security interests of the United States and our allies. So I will veto any legislation that prevents the successful implementation of this deal.

Ahem. It’s not quite consistent to declare oneself welcoming of “a robust debate” while at the same time pledging to ignore everyone else’s advice on the subject of it. Obama isn’t welcoming a debate or scrutiny at all; he’s telling Congress to sit down and shut up. We’re used to Obama being inconsistent and hardline at home, though. We just wish he’d toughen up abroad.

The Senate rejection of the deal under Bob Corker’s bill takes 60 votes, and is almost a certainty. So is Obama’s veto, which everyone understood well enough without the reminder today. Under the Corker bill, that veto becomes subject to an override, which will take 2/3rds of both the House and the Senate. Can the Senate get 67 votes to override Obama’s attempt at legacy-building at the expense of our allies in the Middle East? Bloomberg analyst Greg Valliere says the keys may be Chuck Schumer and Ben Cardin:

Note too the dismissal of John Kerry’s “what if there were no deal” argument as weak tea. “It’s a flawed agreement with an untrustworthy partner,” as one Bloomberg commentator notes, which makes “better than nothing” a ridiculous excuse — and just flat out not true. Nothing would have left sanctions in place, which would have at least curtailed Iran’s ability to fund its terror operations in the region. Jeffrey Goldberg calls the deal a morally dubious necessity anyway: