Two days after Iranian students overran the U.S. embassy in Tehran, taking 66 Americans hostage 30 years ago this month, Pentagon brass met in a secret briefing room called ``The Tank'' to consider rescue options.

Maj. Lewis H. ``Bucky'' Burruss, operations officer for the Army's newly formed counterterrorism unit, Delta Force, outlined an improvised mission that went like this: Parachute a small force to a highway just east of Tehran that would hijack trucks right off the road, drive them into the city, attack the embassy compound, free the hostages and then fight its way 400 miles to the Turkish border. It was tantamount to a suicide mission, for both the rescuers and the American hostages.

``Obviously,'' Burruss said, ``we don't want to do this.''

But this was the best the U.S. military could offer President Jimmy Carter on short notice. In the year and month that followed, many Americans were dismayed by Carter's seeming helplessness. How could the world's premiere superpower be trapped in a standoff with a scruffy band of Islamist college students?

Yet Carter had no military option short of escalating the standoff and almost certainly getting the hostages killed. America was superbly equipped in 1979 to rain missiles on an enemy, and to fight huge tank battles in Eastern Europe, but that was about it. When Carter warned Iran of a swift and harsh response if any hostages were harmed, he convened his generals at Camp David to explore his options if it came to that. He got a roomful of shrugs. After Vietnam, the cupboard had been stripped bare. According to James Kitfield's ``Prodigal Soldiers,'' the Army chief of staff, Gen. Edward ``Shy'' Meyer, told the president, ``Basically what we have is a hollow Army.''

Campaigning against Carter in 1980, Ronald Reagan lost no opportunity to portray his opponent as a timid leader, and to this day, critics of the former president argue that his biggest mistake was not hitting Iran hard and fast. Carter's perceived weakness, aggravated by the abject failure of a Delta rescue attempt he authorized six months later (only slightly less preposterous), is the biggest reason he lost his bid for a second term.

There is a thriving strain of political argument in American life that rests on an unrealistic belief in what force can accomplish. It played a big role in derailing Carter, and it will play a louder role in the coming months if Iran's defiance of nuclear nonproliferation agreements stiffens.

Without a doubt, the U.S. Army and military is ``hollow'' no more. It and the other branches may be overextended and stressed fighting two wars, but President Obama enjoys far better options than Carter did. If the choice is between striking Iran or letting it go nuclear, the president has a wide range of military tools.

But what can force accomplish against Iran's nuclear program? There is little doubt that we could set it back, maybe for years. But that would not eliminate the threat, and would almost certainly stiffen Iran's resolve to proceed. A successful strike would at best buy time, and at great cost.

Apart from certain retaliatory strikes against American forces in the region, against Israel, and within the United States by Iranian agents and its Hezbollah allies, a military strike would likely torpedo the courageous reform effort under way inside Iran. Mahmoud Ahmadinejad's summer electoral victory is widely regarded by his countrymen as fraudulent. Resistance there faces a tough crackdown, but appears to be stubborn.