At the end of another week of near-constant talk about war with Iran, here's one counterintuitive possibility: The Obama administration, in its eagerness to deter an Israeli strike, has committed itself to a pressure campaign that, if pursued vigorously, could eventually lead to regime change in Iran.

President Obama's pledge of escalating economic, political and other pressure on Iran goes to that regime's weak link. For the mullahs' greatest vulnerability is their political structure, which is divided and unpopular, rather than their nuclear program, which appears to have fairly broad domestic support. And this political foundation may be shaken by the campaign that is under way.

The clerical regime isn't an explicit target for the U.S., but it's at growing risk because of the forces now in motion. Month by month, sanctions and other activities will undermine the regime's political and financial base - squeezing the Iranian leadership and tempting it to take rash actions that would trigger a devastating response.

The situation resembles a hunting trap that gets tighter the harder the prey tries to escape. Defense Secretary Leon Panetta made that explicit when he said Thursday that the U.S. was preparing military options should non-military pressure fail.

Ironically, the worst option in terms of regime change would probably be a unilateral Israeli military strike. Given limited Israeli capabilities, a strike would do enough damage to rally political support behind the Iranian leadership (and deflect the Arab Spring) but not enough to cripple the nuclear effort. An Iranian opposition leader told me this week that such an attack would be "a gift from God for the mullahs," enhancing their political position rather than weakening it.

What has emerged from last week's U.S.-Israeli discussions is a sort of tag team: The West is moving toward what it describes as crippling sanctions, while Israel waits restlessly outside the ring, apparently eager to jump in and strike a military blow. This combined pressure has already brought Iran back to the negotiating table, which is welcome, but hardly a reason for the West to back off.

As the sanctions bite deeper into Iran's oil exports and revenues, further enfeebling the regime, Tehran may have to contemplate the kind of negotiated settlement that Ayatollah Khomeini once likened to drinking from a "cup of poison." Or, the regime may lash out with military action of its own - a dangerous course given America's overwhelming retaliatory power and the ability of Israel and Saudi Arabia to absorb Iran's initial punch.

For Iran's Supreme Leader Ali Khamenei, it's a double bind: If he offers a deal on the nuclear program that would be acceptable to the West, he risks undermining what he sees as the regime's legitimacy. But if he doesn't offer a deal, the steady squeeze will continue. Eventually, something's got to give.

Karim Sadjadpour, an Iran expert at the Carnegie Endowment for International Peace whose views are closely studied at the Obama White House, argues that the Iranian regime is gradually bleeding itself to death for the sake of its nuclear program. He likens the process to the demise of the Soviet Union, which bankrupted itself in an arms race with the United States.

Sadjadpour likes to invoke an old saying on the dilemma facing dictators: "While these regimes are in power, their collapse seems inconceivable. But after they've collapsed, we say that it was inevitable." Iran, he argues, is "at the crossroads of that maxim."

Now that the squeeze on Iran has begun, there's a potential risk if it stops too quickly, leaving a damaged but still potent Iran seething for vengeance. That early termination could happen through a quick U.N. cease-fire after a unilateral Israeli strike, or because the West calls off sanctions prematurely, leaving Iran's nuclear tool kit still largely intact.

The West has an additional hidden capability in this crisis, between sanctions and open military conflict. It's a way of increasing the cost of Iran's actions, short of war. Officials don't usually talk about this terrain of "covert action," for obvious reasons, but it's easy to imagine what might be possible: Defense-related research facilities could be disrupted; financial and other commercial records could be scrambled. And these are just the non-lethal options.

"You can cause a lot of mischief inside Iran," says one foreign official. The pressure campaign now under way may not force Iran's current leadership to make a deal, this official notes, but it increases the chance that the regime will sink as a result of its own defiant behavior.