Saul Loeb / AFP / Getty Images US President Barack Obama speaks about the Defense Strategic Review, outlining Defense budget priorities and cuts, during a press briefing at the Pentagon in Washington, DC on Jan. 5, 2012

It’s unlikely that President Barack Obama intends to go to the polls in November with the United States engaged in a hot war with Iran, but there is a growing danger that events could conspire to make the decision for him. The Wall Street Journal reported Friday that “U.S. defense leaders are increasingly concerned that Israel is preparing to take military action against Iran, over U.S. objections, and have stepped up contingency planning to safeguard U.S. facilities in the region in case of a conflict.” Besides planning for the contingency of being dragged into a war started by Israel, the Journal reported that Administration officials from President Obama on down have urged their Israeli counterparts to refrain from unilateral military action. The Israeli response, says the paper, has been “non-committal.” Indeed, Joint Chiefs of Staff chairman Gen. Martin Dempsey is due to visit Israel on Thursday with the purpose, according to Israeli reports, of ascertaining Israel’s intentions.

The Iranians would likely hold the U.S. accountable for any Israeli military action, and any retaliation against U.S. assets (or even attacks on Israel) might prompt the U.S. to escalate the confrontation in order to disable Iran’s military capability — and perhaps strike at its nuclear program in the process. Israel’s leaders would certainly prefer the U.S. to do the job, because its capacity to sustain an air assault on Iran is far greater than Israel’s is. But Israeli leaders have long warned that should Washington fail to stop Iran’s nuclear progress, they might be compelled to take military action alone. Israeli media outlets reported Sunday that a massive joint exercise between the Israeli and U.S. military to simulate countering an Iranian missile attack on Israel will be postponed by Washington, in order to ease the dangerous level of tension that has built up with Tehran in recent weeks.

Restraining Israel from unilateral action by escalating sanctions pressure has been a dominant theme of the Obama Administration’s Iran policy. And current and former Administration officials have said that President Obama would take military action if other methods failed to stop Iran building a nuclear weapon, although the U.S. intelligence assessment is that Iran has not yet decided, let alone begun, to build nuclear weapons despite steadily acquiring the means to do so. But neither Israel’s “bad cop” threats of military action or Washington’s “good cop” sanctions have changed Iran’s calculations, and the nuclear program is steadily expanding its capability. Last week, the International Atomic Energy Agency (IAEA) confirmed that Iran had begun enriching uranium to 20% at its hardened underground facility at Fordo near Qom, a plant built in secret and designed to put some of Iran’s capacity to manufacture nuclear fuel beyond the reach of air attack.

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The latest round sanctions, which aim to stop Iran selling oil and importing gasoline, are being treated by the Iranians as a sign that the U.S. and its partners are seeking to overthrow the clerical regime — an assessment that makes them more likely to seek a nuclear deterrent and less likely to compromise. And their response appears to be to escalate pressures of their own.

The Washington Post caused a stir last week by reporting that it had been told by a “senior U.S. intelligence official” that the goal of the new sanctions was, indeed, to bring down the regime in Tehran. The paper quickly corrected itself — presumably after the alarm bells sounded in the Administration, which can’t afford to seen to be pressing for regime change either by the Iranians with whom it may be trying to negotiate, or by the Europeans and others whose support it is enlisting for sanctions. In the revised version, the purpose of the sanctions was stated as to “create hate and discontent at the street level so that Iranian leaders realize that they need to change their ways.” The difference, of course, may be so subtle as to have little practical meaning: It makes clear that the sanctions are specifically aimed at undermining the well-being of ordinary Iranians, in the hope that they will direct the resultant anger at their government — essentially, a repeat of the strategy used by Israel in blockading Gaza in the hope that economic pressure on the citizenry would result in the ouster of the territory’s Hamas rulers.

Israel’s Gaza blockade strategy failed, of course, and the hope that squeezing their livelihoods will prompt ordinary Iranians to overthrow their regime or press it to change course may be just as fanciful. Writes Hooman Majd, “the Iranian people, from my greengrocer to college students who resent their government, still consider the nuclear question in generally nationalistic terms… So sanctioning Iran’s central bank and embargoing Iranian oil, tactics the White House may be using as a way to avoid having to make a decision for war, will neither change minds in Tehran nor do much of anything besides bring more pain to ordinary Iranians. And making life difficult for them has not, so far, resulted in their rising up to overthrow the autocratic regime, as some might have hoped in Washington or London.”

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President Obama appears to have little say over whether Israel attacks Iran, but even his control over U.S. sanctions policy may be less than he might like. Last month, sanctions that effectively blockade all of Iran’s international trade through imposing sanctions on third-country corporations that do business with Tehran’s central bank, were adopted by an overwhelming majority in both chambers of Congress — despite the Administration’s misgivings. The purpose of those sanctions, routinely described as “tightening the noose” by State Department officials, is to choke off Iran’s economy. In an election year in which painting Obama as weak on Iran is the centerpiece of the Republican foreign policy discussion, and with congressional Democrats far more hawkish on the issue than the White House is, putting the brakes on a sanctions policy to which Iran may respond as if to an act of war carries a heavy political cost to the president.

And if sanctions and Israeli air strikes are two potential triggers for war over which the White House has less than optimal control, it may have even less say over the covert war against Iran that could could also provoke full-blown hostilities.

The realization that the Administration’s options are being narrowed by the actions of others may account for the vehemence with which Secretary of State Hillary Clinton last week condemned the murder of an Iranian nuclear scientist in Tehran. The general assumption, both in Tehran and in Western capitals, is that Israel is behind the attacks — a suspicion reinforced by the Israeli response which has been to effectively encourage it without claiming — or denying — responsibility.

Even more alarming, if true, were the claims made in Foreign Policy magazine by military analyst Mark Perry, last week, alleging that an internal CIA assessment had concluded that Israeli Mossad agents masqueraded as CIA operatives while recruiting members of a Sunni jihadist group to wage proxy operations in Iran. An anonymous Israeli official speaking to Haaretz dismissed the charge as “absolute nonsense,” while U.S. officials did not comment for Perry’s story.

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First and foremost among those who could take the decision to start a war out of Obama’s hands, of course, are the Iranians.

“We should not be surprised that a country faced with economic warfare would remind the world that it, too, can create mischief,” warns former National Security Council Iran specialist Dr. Gary Sick. “Iran cannot close the Strait of Hormuz for a prolonged period of time, but it is capable of impeding oil traffic out of the Persian Gulf for many months. The loss of its own oil exports would be the trigger for such action, which would drive up the price of oil to unforeseeable levels and risk a wider regional war.” (Other analysts suggest that closing the strait may be Iran’s trump card, which it would hold in reserve for when it comes under military attack, and might instead seek other methods of retaliation for sanctions pressure.)

Defense Secretary Leon Panetta has repeatedly warned Iran that closing the Strait, through which some 40% of global oil traffic passes, is a “red line” that would draw a military response. The New York Times reported Friday that the U.S. had used a secret channel to send that same message to Iran’s Supreme Leader, Ayatullah Ali Khamenei. But if the message is simply that Iran had better surrender or else sit still while the West chokes off its economic lifeblood, it might as well haven been delivered through a bullhorn. The key question is whether these “secret channels” are being used to communicate anything besides threats.

Until now, the “diplomatic” conversation between the Administration and Iran has largely been restricted to ultimatums, with neither side showing signs of buckling. Turkey appears to have brokered a new round of talks between Iran and the Western powers plus Russia and China. And Iran has agreed to receive a new delegation of IAEA inspectors (besides those who permanently monitor Iran’s enrichment activities), although the extent of cooperation Tehran plans to offer remains to be seen.

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“The central problem is that this is a zero-sum diplomatic game and each side’s move are inherently dual-use and therefore subject to the most malign interpretations,” warns Shashank Joshi, an analyst at Britain’s Royal United Services Institute. “Enrichment is seen as synonymous with weaponisation, and sanctions are seen as tantamount to regime change. All the while, Tehran has negotiated in obviously bad faith, but the U.S. has also shown little willingness to take risks or offer up carrots commensurate with the sticks.” Domestic politics on each side also militate against making confidence-building concessions to the others. “That is where we stand,” writes Joshi. “Diplomacy that hasn’t worked, sanctions whose effects are unpredictable, and each side lashing themselves ever tighter to the mast.”

Finding a diplomatic path out of the crisis has become increasingly urgent in the eyes of some in Washington — where the U.S. military establishment believes that a military confrontation will do more harm than good, and will at best only delay Iran’s progress but make weaponization more likely — and in allied capitals. But diplomatic solutions would require compromises unlikely to appeal to more hawkish voices, and getting there would require a protracted process of talking and confidence-building gestures that defy the minutes-to-midnight clock imposed on the standoff by those pressing for tougher action. And the track record of the Iranian leadership suggests that covert warfare and effective sanctions are more likely to push them to respond with escalations of their own rather than with concessions.

For pessimistic hawks — those who believe military action is inevitable, and necessary, unless Iran caves on its nuclear program — squeezing Iran to the point that it initiates such hostilities is not necessarily a policy failure. Asked that question by Yahoo columnist Laura Rozen, Patrick Clawson of the hawkish Washington Institute for Near East Policy explained, “I think it’s heading towards confrontation,” Clawson said. “The whole point from the beginning is if we put pressure on the regime, the Iranians will crack at some point.” If there is to be fight, he explained, it’s preferable that it be initiated by Iran, adding by way of anaology, “Better to enter World War II after Pearl Harbor.”

Pearl Harbor, of course, allowed President Roosevelt to enter a war he’d been trying to join. But an Iranian equivalent would plunge President Obama, despite himself, into a war he’d hoped to avoid.

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