What if there’s no Iran deal?

No deal is better than a bad deal, say critics of President Barack Obama’s nuclear talks with Iran.

But what if Republican and Democratic opponents succeed in their intensifying effort to derail the diplomacy?

The price of failure could be an ugly blame game and cascade of political reprisals leading to nuclear chicken between Iran and the West — potentially leading to war.

“We would have to deal with a resumption of Iran’s nuclear activities, which we don’t want to see take place. Iran would have to deal with the resumption of sanctions, which they don’t want,” said Gary Samore, a top nonproliferation official during Obama’s first term.

For now, the grave consequences of a breakdown in talks are one reason the United States and Iran are still at the table, as a grueling diplomatic process reaches critical deadlines and painful political decisions beckon.

Secretary of State John Kerry and Iranian Foreign Minister Javad Zarif are haggling over the remaining issues in Lausanne, Switzerland, ahead of an end-of-the-month deadline for a framework agreement, which then must be finalized by July 1.

But time may be running out for a deal in which six world powers would lift sanctions that have throttled Iran’s economy in return for assurances that Tehran will continue to stay a year or so away from developing a nuclear bomb.

The White House puts the chances of a deal at only 50-50: Disputes still rage over the scale of nuclear infrastructure Iran will be allowed to keep, the pace of sanctions relief and the extent of nuclear site inspections.

Despite the controversy stoked last week in Washington when 47 GOP senators sent a letter to Iran’s leaders warning that the future of a deal was not guaranteed, many analysts believe that the talks will go on, even if the end-of-March deadline slips.

Obama may now have slightly more political leeway on the talks than before — ironically because of attempts by U.S. and Israeli critics to pen him in.

A few weeks ago, skeptical Democrats appeared to be lining up with Republicans and approaching a veto-proof Senate majority that could have forced Obama to submit a deal to Congress or accept the passage of new sanctions. Either move could have killed the agreement.

But the Republicans’ letter and a fiercely critical speech to Congress by Israeli Prime Minister Benjamin Netanyahu on the proposed deal prompted some skeptical Democrats to close ranks, at least temporarily.

If diplomacy fails, how events unfold will be dictated by how the process collapses; who gets the blame; and the political pressures exerted on Obama and Iranian President Hassan Rouhani in Washington and Tehran.

“If, at the end of June, there is not a deal, and talks have broken off, I think that it is inevitable that the Congress will adopt new sanctions legislation,” said Einhorn, now with the Brookings Institution.

“What that will mean is the Iranians will reciprocate.”

Iran could start up centrifuges halted during the nuclear negotiations, bring more advanced machinery online and enrich uranium to the potent 20% level that would get it closer to a weapon.

And if it bars international inspectors, the world would have no idea how far Iran is from making a bomb.

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