A president desperate to change the subject and a secretary of state desperate to make a name for himself are reportedly on the verge of an “interim” nuclear agreement with Iran. France called it a “sucker’s deal.” France was being charitable.

The only reason Iran has come to the table after a decade of contemptuous stonewalling is that economic sanctions have cut so deeply — Iran’s currency has collapsed, inflation is rampant — that the regime fears a threat to its very survival.

Nothing else could move it to negotiate. Regime survival is the only thing the mullahs value above nuclear weapons. And yet precisely at the point of maximum leverage, President Barack Obama is offering relief in a deal that is absurdly asymmetric: The West would weaken sanctions in exchange for cosmetic changes that do absolutely nothing to weaken Iran’s nuclear infrastructure.

Don’t worry, we are assured. This is only an interim six-month agreement to “build confidence” until we reach a final one. But this makes no sense. If at this point of maximum economic pressure we can’t get Iran to accept a final deal that shuts down its nuclear program, how in God’s name do we expect to get such a deal when we have radically reduced that pressure?

A bizarre negotiating tactic. And the content of the deal is even worse. It’s a rescue package for the mullahs.

It widens permissible trade in oil, gold and auto parts. It releases frozen Iranian assets, increasing Iran’s foreign-exchange reserves by 25 percent while doubling its fully accessible foreign-exchange reserves. Such a massive infusion of cash would be a godsend for its staggering economy, lowering inflation, reducing shortages and halting the country’s growing demoralization. The prospective deal is already changing economic expectations. Foreign oil and other interests are reportedly preparing to reopen negotiations for a resumption of trade in anticipation of the full lifting of sanctions.

And for what? You’d offer such relief in return for Iran giving up its pursuit of nuclear weapons. Isn’t that what the entire exercise is about?

And yet this deal does nothing of the sort. Nothing. It leaves Iran’s nuclear infrastructure intact. Iran keeps every one of its 19,000 centrifuges — yes, 19,000 — including 3,000 second-generation machines that produce enriched uranium at five times the rate.

Not a single centrifuge is dismantled. Not a single facility that manufactures centrifuges is touched. In Syria, the first thing the weapons inspectors did was to destroy the machines that make the chemical weapons. Then they went after the stockpiles. It has to be that way. Otherwise, the whole operation is an exercise in futility. Take away just the chemical agents, and the weapons-making facilities can replace them at will.

Yet that’s exactly what we’re doing with Iran. It would deactivate its 20 percent enriched uranium, which besides being chemically reversible, is quickly replaceable because Iran retains its 3.5 percent uranium, which can be enriched to 20 percent in less than a month.

Result: Sanctions relief that leaves Iran’s nuclear infrastructure untouched, including — and this is where the French gagged — the plutonium facility at Arak, a defiant alternate path to a nuclear weapon.

The point is blindingly simple. Unless you dismantle the centrifuges and prevent the manufacture of new ones, Iran will be perpetually just a few months away from going nuclear. This agreement, which is now reportedly being drafted to allow Iran to interpret it as granting the “right” to enrich uranium, constitutes the West legitimizing Iran’s status as a threshold nuclear state.

Don’t worry, we are assured. The sanctions relief is reversible. Nonsense. It was extraordinarily difficult to cobble together the current sanctions. It took endless years of overcoming Russian, Chinese and Indian recalcitrance, together with foot-dragging from Europeans making a pretty penny from Iran.

Once the relaxation begins, how do you reverse it? How do you reapply sanctions? There is absolutely no appetite for this among our allies. And adding back old sanctions will be denounced as a provocation that would drive Iran to a nuclear breakout — exactly as Obama is today denouncing congressional moves to increase sanctions as a deal-breaking provocation that might lead Iran to break off talks.

The mullahs are eager for this interim agreement with its immediate yield of political and economic relief. Once they get it, we will have removed their one incentive to conclude the only agreement that is worth anything to us — a verifiable giving up of their nuclear program.

Brilliant.

Charles Krauthammer, a Pulitzer Prize-winning syndicated columnist, writes a weekly political column for The Washington Post. Email to letters@charleskrauthammer.com.