On Monday, the Foreign Ministers of Iran and the 5+1 Powers announced that they had failed to reach a comprehensive nuclear deal before a midnight deadline. Instead, they had agreed an extension of interim arrangements over Iran’s nuclear program until July 1, so talks could continue.

That’s the simple story. What’s far more important to establish are the details of the failure in Vienna — and what is likely to happen over the next seven months.

1. THERE WAS NO DEAL IN NOVEMBER, AND THERE WILL BE NO DEAL BY JULY 1

Unsurprisingly, diplomats from Iran and the 5+1 (US, Britain, France, Germany, China, and Russia) all declared “progress” even as they said no agreement had been confirmed. To do otherwise would have been to bury years of discussions and to face the uncertainty of confrontation.

But those statements could not cover up the fundamental division, and they cannot offer any prospect of resolving it by July 1.

Iran wants to expand its program of enrichment of uranium to 20% for civilian purposes. Currently, that enrichment is provided by about 10,000 centrifuges; another 10,000 are installed but are not yet operational. Expansion would come through:

1. Expansion of the number of centrifuges;
2. Introduction of the more advanced IR-2m centrifuges, and development of the IR-5 model, to replace the 40-year-old IR-1s;
3. Both.

The US and European partners insist on a reduction of the Iranian program:

1. Decrease in the number of centrifuges to between 6,000 and 7,000;
2. No introduction of any models beyond the IR-1s.

Years of negotiations will not resolve those opposed positions. The Iranians will not stand on the Supreme Leader’s goal of a 20-fold increase in capacity, but any long-term “freeze” — let alone a reduction — would be a smack-down of their oft-proclaimed right not only to a nuclear program but one which they say is sufficient for civilian needs.

In theory, a way out would be an iron-clad guarantee of enrichment of Iran’s uranium by another country, for example, Russia. In practice, the possibility of the solution is dim. Russia already is contracted to provide the fuel for Iran’s Bushehr nuclear reactor until 2021, but Iran — which has a history of tension over arrangements with Moscow — does not trust that the existing deal will hold for the next seven years, let alone be extended. And the Western proposal probably goes much farther: it is calling on Iran to entrust the large majority of its uranium supply to the Russians.

2. IRAN WILL NOT “BREAK” THE NEGOTIATIONS

However, it will not be the Iranians who step away from the negotiating table. Despite his entrenched distrust of the Americans, the Supreme Leader continued to back the Rouhani Government’s pursuit of a deal all the way to Vienna. He will do so beyond it.

What’s more, Ayatollah Khamenei will tell hard-line opponents of any further talks to be quiet. That was the message given to MPs by the Speaker of Parliament, Ali Larijani, on Sunday in a closed-door session.

Some analysts had predicted that failure in Vienna, even with an extension, would bring the eclipse of the “moderate” President Rouhani as his opponents scoffed at his weakness before the Americans. However, this morning the outlets of the Revolutionary Guards, hardline MPs, and the Supreme Leader put out no such criticism.

Why?

The diplomatic reason is that Iran wants to pin any final breakdown on the Americans. Facing key contests for opinion in the Middle East and in the “non-aligned” world and wanting to secure relations with key political and economic partners like Iran and China, Tehran will maintain that it is the “positive” power seeking agreement.

But the bigger reason may be economic. A lasting failure in the talks brings years of even tougher sanctions on an economy which is reeling from long-term falls in investment and productivity, now compounded by a sharp drop in the global oil price.

The Supreme Leader may hold up his “resistance economy” as an alternative, but even he probably knows that is an alternative of sacrifice and hardship, rather than progress.

So on Monday, the 5+1 Powers gave Tehran a small gesture of economic relief — $4.2 billion in unfrozen assets over the six months — in return for the extension. And Iran quickly accepted.

3. BUT CRITICISM FROM THE US WILL CRIPPLE THE TALKS

A well-placed EA source noted wryly on Monday, “President Rouhani is in better shape with his people than President Obama is with his.”

That may be a tad dramatic, but the immediate fallout of Monday’s news will be a spike in commentary from hard-line US critics of any deal with the Islamic Republic.

The campaign was already underway last week, with favored outlets such as the Foundation for the Defense of Democracies, the Institute for Science and International Security, United Against a Nuclear Iran, and the American Enterprise Institute putting out their demands for even tougher sanctions in the guise of “analysis”. They did so both to welcoming media — The New York Times has been especially forthcoming in publication of headline stories — and to a Congressional committee.

Expect more and louder. In January, the new Congress will have a Republican majority in both houses. That will not guarantee passage of further sanctions against a veto by President Obama, but it will definitely block any removal of sanctions that are in existing legislation.

Put bluntly: even if President Obama and his advisors would accept a limited expansion of Iran’s uranium enrichment, Congress will not — in January, July, or a date far, far away.

4. SO WHAT NOW? BRINGING IRAN TO ITS KNEES

So if there is no prospect of a compromise and if neither side wants to end the talks, what now?

For years, the US strategy has been one of economic pressure to bring Iran to the negotiating table and to get the terms that Washington wants.

To an extent, that has worked. It re-opened talks in autumn 2009 after Tehran faced a shortage of uranium. It spurred them in 2012, as the European Union added a tough set of sanctions to those of the Americans and the UN, and — most importantly — it persuaded the Supreme Leader in autumn 2013 that he had to support the Rouhani Government’s “engagement”.

But the economic pressure — combined with the salves of public recognition of an Iranian nuclear program — could not push through the comprehensive nuclear agreement.

One lesson might be that, in the end, you can’t just bludgeon the Iranians into a settlement. You might have to recognize not just the right but some of the practical arrangements for their program, in conjunction with a well-defined system of inspection and supervision by the International Atomic Energy Agency.

That won’t be the lesson “learned” by Washington, even if some official believed it — the domestic politics will not allow any further compromise.

Instead, the US lesson will be that it must tighten the economic screws, waiting for Iran to cry Uncle and accept the reduction in its enrichment capacity.

That is why the extension was surprisingly long. The Americans and their partners know that the Supreme Leader will not buckle in coming days or weeks.

But they think that maybe, just maybe, even Ayatollah Khamenei will accept over months that he cannot subject his people to more hardship. And then he will finally drink from the “poisoned chalice” of an agreement that constrains the Islamic Republic’s nuclear program for years to come.