The Post reports: “Iran and the U.N. nuclear watchdog agency are near agreement on a plan that could lift the veil on some of the Islamic Republic’s past nuclear research, U.N. officials said Tuesday in an announcement that raised hopes for a more comprehensive nuclear accord when Iranian officials meet with six world powers later in the week.”

There is far less to this development than the United Nations, the Obama administration and the Iranians — all working to prevent an Israeli strike — may tell us.

Mark Dubowitz of the Foundation for Defense of Democracies, who has been involved in crafting sanctions, isn’t bowled over. He tells me: “The trick in negotiations is to make it appear that a concession wanted by your opponent is much more important to you than it really is. Then you can trade it away for a reciprocal concession of greater value.”

In reference to the Parchin nuclear site that could be opened up to inspectors, Dubowitz explains: “Iranians elevated its importance by stubbornly refusing to allow IAEA access. Now that they may allow access, the response will be that this is a major concession requiring the [the United States and its allies] to give real sanctions relief. Oldest trick in the book.”

In a broader sense, all of this is window dressing, seeing what can fly as a genuine deal. A senior Capitol Hill aide involved in Iranian issues agrees, “The Iranians are trying to position themselves for Baghdad, trying to create the appearance that they are ready to deal, without [as of yet] offering any real concessions.”

But it’s not so easy to come up with something meaningful. The aide observes, “The question for the Israelis isn’t as simple as whether the Iranians are currently enriching [uranium] or not. It’s much broader — about whether the program is getting hardened, dispersed, expanded and more technologically advanced. The Israeli fear is that they will find themselves at a point in the near future when they no longer have the military capability to inflict serious damage on the program — the [Defense Minister Ehud] Barak concept of a ‘zone of immunity’ — while at the same time the Iranians have successfully collapsed the time needed to break out, because they have continued growing the quantity and sophistication of the centrifuge cascades they have installed.”

He cautions, “If Iran continues its progress in that direction, the Israelis are going to be under growing pressure to strike before it is too late. Even assuming that the Iranians agree to suspend operations at Fordow, stop enrichment at 20 percent, and ship out the existing stockpile of 20 percent — a tall order — this won’t alone be sufficient to change that dynamic.”

We are at this point because despite sanctions Iran has made steady progress with its program. Had President Obama not wasted 18 months at the onset of his term “engaging” Iran and then slow-walked up to serious sanctions (dragged every step of the way by Congress), we might be in a better position. But because we have let Iran slide ever closer to the “zone of immunity,” military action is becoming the only option, other than acceptance of a nuclear-armed Iran.

If Israel is forced to act militarily, it will be because Obama’s sanctions policy failed and he refuses to make good on his vow to use “all options” to prevent Iran from acquiring a nuclear weapons capability.