In remarks to American Jewish leaders on Friday, Israel's man in Washington, Michael Oren, gave a certain cautious welcome to the results of the previous day's first direct Iranian-American diplomatic engagement on Iran's nuclear program. Teheran's readiness to open its Qom enrichment site to IAEA inspectors and its apparent willingness to have other countries process its enriched uranium for ostensible peaceful use, said the ambassador, could be considered "important and rather positive developments." It would be a mistake, however, to read any genuine sense of Israeli relief, much less pleasure, into that kind of polished diplomatic response. Oren's comments merely reflect Israel's decision to publicly endorse President Barack Obama's attempt at diplomacy, even though there is utter certainty in Jerusalem that Iran is playing for time and will not be talked out of the bomb. Oren spelled out, tellingly, that Israel was backing the effort at engagement on condition that the talks with Teheran "not be open-ended, that there would be an eye on the enrichment clock, which continues to tick." Indeed it does. And there can only be heightened concern in Jerusalem that the headlines from Geneva, hailing the apparent positive headway made at the engagement talks there, are obscuring this immensely troubling fact. What happened in Geneva was that Iran grudgingly accepted inspection of a facility it had constructed in secret, and is now presumably rendering inoffensive ahead of those checks, and it agreed in theory to have its uranium enriched overseas - a concession it is now disputing and no great hardship anyway. What didn't happen in Geneva was anything that moved Iran any nearer to freezing enrichment - that is, to halting its serene path to nuclear weapons. Indeed, Iran has been unprepared to so much as discuss halting those parts of its program that are slowly but surely bringing it to the status of a nuclear threshold nation. The flawed nature of the Nuclear Non-Proliferation Treaty is that states can claim to be working within its framework and complying with its requirements while hauling themselves to the very brink of nuclear weapons capability - ready to "break out" to the bomb in a matter of months, if not weeks. It has long been Israel's conviction that this is the Iranians' game plan: stay more or less within the parameters of the NPT until they have reached that threshold, and then, at the moment of their choosing, aided with progress made at various non-disclosed facilities, breach the treaty and go nuclear when it's too late for anyone to stop them. Israel never accepted the dramatic assertion in the 2007 US National Intelligence Estimate that Iran had halted its nuclear weapons program. Indeed, Jerusalem is convinced that by now, neither delivery systems nor weaponization constitute serious obstacles to an Iranian bomb. That's why, from Israel's point of view, Iran must be denied sufficient quantities of sufficiently enriched uranium to make that final push for the bomb. The "break out" capacity must be prevented. Curiously, Oren's was a lone official Israeli voice responding to Geneva. The silence from Jerusalem was deafening. And whatever the ostensible "important and positive" developments at the talks, the fact is that so long as Iran keeps those centrifuges spinning, the window on diplomacy, from Israel's point of view, is closing by the day.