The second-in-command of the world’s greatest state sponsor of terrorism is coming to New York. Cause for celebration?

Hassan Rouhani is Iran’s new president, chosen in an undemocratic election. Rouhani has spent his life in the service of the Islamic Republic, and there is no evidence anywhere of dissent. If he opposed jailing dissidents, killing opponents, supporting terrorism by Hezbollah and others, killing Americans in Iraq and Afghanistan, stealing elections, and trying to build a nuclear weapon there is no evidence of it. But Rouhani is famous for one thing: pulling the wool over Western eyes and negotiating at length to provide year after year for Iran to move closer to having nukes.

This being the case, the wondrous glee with which his Washington Post op-ed is being received in some quarters is remarkable. It is as if Iran’s new non-leader – for remember, the Supreme Leader is Ayatollah Khamenei, not Rouhani, whose powers are entirely untested – were Neville Chamberlain, desperate for peace and seeking any available compromise.

Unfortunately for us, Rouhani arrives in New York at a moment of Western and especially American weakness. Who can believe, today, that “all options are on the table” when it comes to stopping Iran? Who can believe that the president who flinched over Syria will take on the far more challenging task of attacking Iran? With the military option devalued, Iran’s incentives to make a deal are reduced – meaning that its negotiating position will be that much tougher. And Iran’s officials have just seen the United States bamboozled by Russia into a chemical-weapons deal on Syria that no expert believes is credible and enforceable. By the end of its first week that deal had been violated by Syria, which missed the first deadline it faced – with no American or other Western reaction. If Syria can delay and distort and lie, and keep some of its chemical weapons, why can’t Iran do a similarly advantageous deal? To Tehran, Obama must seem like a man cornered, caught between his repeated pledges to stop Iranian progress to a bomb and his desperate desire to avoid another Middle East war. Just as Russia offered him a way out in Syria, so Iran itself will likely now offer a way out: a negotiated deal of equal value.

We know what we need in an Iran deal: to move Iran farther away from having nuclear-weapons capability. That means conditions like stopping enrichment, stopping conversion of old to new centrifuges, exporting previously enriched uranium, closing the Fordo underground site, stopping the plutonium path to a bomb via the heavy-water plant at Arak, permitting thorough unannounced inspections, accounting for all previous nuclear work, and stopping work on a warhead. The likelihood that Iran will today agree to these conditions, and to the IAEA’s and U.N. Security Council’s current demands, is near zero. So the question is, what compromises will the United States be willing to accept? Rouhani is smart enough to know that a honeyed tongue will help him, and those in the American media who are desperate to believe him accept far less.

Will the president meet Rouhani at the U.N.? They are not counterparts, because Obama is head of government and head of state, while Rouhani is subservient to the Ayatollah. A smiley handshake will telegraph that all is, if not forgiven quite yet, about to be forgiven: the terrorism, the intervention in Syria, the vicious repression at home.

Here’s a better route. Obama should say he doesn’t want to meet the representative of the leading supporter of terrorism, and the chairman of the joint chiefs should say he is fully confident that an American attack on the Iranian nuclear sites would destroy them all in short order. Then our negotiators should say they look forward to the next P5+1 meeting.

That’s the path to a serious negotiation.