Will the Obama administration urge Israel to halt settlement building, in order to help create a regional climate more conducive to pressuring Iran?

It's not clear what had delayed the much-anticipated appointment of former Clinton administration special Middle East coordinator Dennis Ross, finally announced in mid-week, as the State Department's new point man on Iran.

Actually, it's still not absolutely clear that Ross is Secretary of State Hillary Clinton's point man on Iran, since he has formally been designated her "special adviser for the Persian Gulf and Southwest Asia."

The carefully formulated title would appear to have been designed specifically not to contain the word "Iran," perhaps because of turf-war sensitivities within the administration, and perhaps because the naming of the Jewish, Zionist Ross - founding chairman of the Jerusalem-based Jewish People Policy Planning Institute - is something of a red rag to the Teherani bull.

As weeks went by without Ross being named to the job, it was speculated variously that the Obama administration might be preparing to capitulate to Iran by freezing him out, that it was taking time to formulate his specific brief and especially the division of responsibility and authority between him and the Obama peace envoy George Mitchell, and even that the premature celebration of his appointment by some of Ross's friends and colleagues might have torpedoed his chances.

Now that he is on board, however, his slightly belated arrival adds weight to the new president's repeated pledge (including to this newspaper when candidate Obama, with Ross at his side, visited Israel last July) to do everything in his power to prevent Iran attaining a nuclear weapon. For Ross clearly shares Obama's declared assessment that this terrible regime must be prevented from attaining that terrible weapon. It's just that, as Defense Minister Ehud Barak warned on Wednesday, time is running out...

WITH ITS hyped commencement of pilot operations at the German-started, Russian-completed nuclear reactor at Bushehr on Wednesday, Iran continued its strategic effort to persuade the deplorably hesitant watching world that it's all too late - that the Islamic Republic has passed the point of nuclear no return, and that no amount of international pressure can now stop it. Gholamreza Aghazadeh, the head of the Atomic Energy Organization of Iran, made that "fait accompli" gambit explicit, bragging that "America should face reality and accept living with a nuclear Iran."

Even though Barak insisted that Israel remains adamant in its determination to ensure Iran not go nuclear, and is "not ruling out any option," the Iranians' strategy may be paying dividends. "If they were not stopped until now," allowed a senior Israeli defense official quoted in this newspaper on Thursday, "it is very possible that Iran will succeed in becoming a nuclear country."

In private conversation, senior American officials and politicians will readily acknowledge that the ridiculously sanguine 2007 National Intelligence Estimate killed off the prospect of the Bush administration taking military action to stop Iran. A little less readily, they will acknowledge that if all else fails it will be Israel or nobody who does act.

Within Israeli circles, meanwhile, the public rhetoric is as robust as ever. Barak's comments underlined this, and stopping Iran is a declared top priority for Binyamin Netanyahu. The question is whether, should push come to shove, the next prime minister would indeed order in the IAF - on a mission immensely more complicated than the strike at Saddam Hussein's Osirak reactor in 1981.

Twenty-eight years ago, no one knew Israel could fly the distance. Its target was a single, inadequately protected facility. There was little likelihood that Iraq could rebuild, and no great danger of Iraqi retaliation. None of these factors applies in the case of Iran, and should the Russians agree to let Iran protect the infrastructure they have so recklessly helped to build with S-300 missile defenses, the logistics of an air strike become infinitely more complex still.

When interviewed for this column last September, Ross endorsed the Bush administration's already-evident decision not to strike at Iran, arguing that there was still time to intensify economic sanctions and deter the mullahs.

"Iran has an array of very profound economic vulnerabilities and we haven't been playing upon them," he lamented. "The US Treasury has probably been the most effective. But you need a more collective approach. The Iranians' oil output is declining and their consumption is growing. The export of oil is the key revenue the regime uses to buy off the Iranian public. Pressure that and you pressure the leadership."

But Ross also cautioned even then that "we don't have a lot of time. The sooner you begin to effect real economic sanctions, the sooner they'll have to make hard choices."

Indeed, in an interview he gave elsewhere back in July 2007, Ross had spoken of a deadline "18 months from now, when Iran's air defense system, which is being upgraded by the Russians, will be completed. That will make it much more difficult to successfully strike Iran's nuclear capacity from the air.

"The closer we get to that window without resolution of the Iranian nuclear problem, the more Israel will feel compelled to strike," he said. "Clearly, at the moment, we are headed down the path of use of force. The slow-motion diplomacy of the West simply does not match the rapid development of Iran's nuclear capacity and the closing window when Iran's upgraded air defenses will be in place."

Those 18 months will be up in March, and whether or not Ross was figuring the S-300s into his equation, plainly there's precious little wiggle room left today.

When I asked him, in our September interview, which specific steps he most urgently recommended, Ross urged working with the European Union "to cut off the oil and industrial gas, and cut back the provision of refined products" to Iran. He also suggested co-opting the Saudis. "China's stake in Saudi Arabia dwarfs its stake in Iran," he noted. "The Saudis don't want Iran to go nuclear. And if you line up the EU and China, that might [in turn] build a Russian incentive to be more responsible."

RUSSIA'S SENSE of responsibility evidently did not deter it from bringing Bushehr toward completion. We wait to see whether it will prevent Moscow from shipping the S-300s.

But Ross's comments about encouraging the Saudis to help ratchet up pressure on Iran were echoed in private conversations I have had in the last few days with several knowledgeable American sources.

According to one scenario put to me, the Obama administration will be taking a comprehensive approach to the Middle East - attempting to broker Israeli-Palestinian progress for both direct benefit and to create a more conducive environment for pressuring Iran. This scenario envisages a major American effort, to be launched with full presidential weight in the coming weeks, and possibly featuring a presidential visit to the region.

It would likely include a demand for an Israeli settlement freeze - a complete halt to building, that is, with no natural growth - as both an extension of longstanding American opposition to the settlement enterprise and as an ostensibly critical step toward bolstering Mahmoud Abbas's credibility and room for negotiating maneuver.

How that demand would go down with a narrow, right-wing coalition - the only coalition Netanyahu currently seems capable of forming - is readily imagined. But, it was put to me, the administration's argument to Netanyahu would be that Israel's principal concern is thwarting Iran; thwarting Iran requires regional cooperation; Israeli readiness to halt settlement and ideally even accept the Saudi peace plan as a basis for negotiation would catalyze such regional cooperation, including via the Ross-advocated Saudi pressure on China; and Israel's own declared interests, in any case, require a viable accommodation with the Palestinians.

If such a scenario were indeed to play out, new prime minister Netanyahu could be faced with the acutely unenviable choice of defying America to maintain a narrow, pro-settlement coalition, or defying his domestic political partners and many of his voters for the sake of an international partnership to try to stop Iran.

MANY AMERICAN political leaders, firm Israel supporters among them, it might be added at this point, are somewhat bemused, to put it mildly, by some of Israel's policies and actions these days. Specifically, they wonder why Israel, since it regards the Hamas governance of Gaza as strategically untenable, chose to continue Operation Cast Lead beyond the initial air strikes but not so far as to achieve the Hamas-humiliating "victory picture" of IDF tanks deployed in the heart of Gaza City.

Furthermore, they ask in similar vein, why would Israel now contemplate hugely boosting Hamas by releasing hundreds of the Islamists' most notorious - and thus most prized - security prisoners? Especially when among those slated for release in a deal for Gilad Schalit are numerous Hamas politicians, who will immediately initiate parliamentary activity designed to destroy the legitimacy of Abbas's problematically extended presidency.

Last week's first visit to Gaza in eight years by US congressmen, meanwhile, produced criticisms of Israel rarely heard from prominent American politicians. While Keith Ellison and Bruce Baird are hardly representative of the mood on Capitol Hill, where near wall-to-wall support for Israel is a given, they are not without credibility among their colleagues. Their depiction of Israel's purported disproportionate use of force is resonating even among legislators who are instinctively sympathetic to Israel and who strongly doubt that the Gaza visitors were shown a remotely full and fair picture.

Baird has expressed horror at "the level of destruction, the scope of it, the civilian targets," and urged his government to reconsider its military aid and weapons sales to Israel. And the first-hand testimony of Ellison, the first Muslim member of Congress, may garner a particularly wide and eminent audience.

AT THE very least, it can safely be said that the combination of Operation Cast Lead and the Israeli election results are unlikely to have reduced any readiness on the part of the administration to pressure Israel to do its bit on the matter of settlements, and thus to help Israel itself and the wider community enable a ratcheting up of pressure on Iran.

The Obama-championed comprehensive Middle East drive, I should stress, was just one prediction set out for me. But the linking of Israeli-Palestinian progress to the battle against Iran is widely discussed in international diplomatic circles.

The newly appointed Dennis Ross may or may not see value in the connection. When we spoke in September, he profoundly (and as it unsurprisingly proved, rightly) doubted the Bush-Olmert contention that the gulfs between the Israeli and Palestinian negotiating positions were close to being bridged. Ross may well also doubt that a Palestinian partner is capable of meeting even the most willing Israeli government halfway down the road to peace.

But Ross, of course, has no direct role in Israeli-Palestinian negotiations. He is the curiously titled "special adviser for the Persian Gulf and Southwest Asia." George Mitchell holds the Middle East envoy's portfolio now. And Mitchell arrived here on Thursday for the second time in a month, to be followed next week by their boss, Secretary of State Clinton.