Just over a quarter-century ago, five Iranian college students hit upon the idea of seizing the U.S. Embassy in Tehran and staging a sit-in. Among them were Iran's Mahmoud Ahmadinejad, who is now Iran's president, and Habibollah Bitaraf, now energy minister. The takeover of the embassy did not play out exactly as its student planners envisioned — indeed, Ahmadinejad himself initially opposed the move — but as a symbolic step, it not only isolated Iran from the rest of the world, it also rallied millions of Iranians to the idea of a strictly Islamist future. The ensuing hostage crisis made a big splash internationally, but perhaps its most important and lasting consequence was local: It gave the mullahs the leverage to take full power.

It is an old political strategy: Identify a foreign enemy, provoke a crisis and wrap yourself in the flag. Today's confrontation with Iran over nuclear research is an example of how, as the saying goes, history rhymes.

Hard as it may be for Americans to believe, in November 1979 Iran's theocratic future was hardly assured. There had been a revolution, of course, but many different forces had combined to overthrow Shah Mohammed Reza Pahlavi. The mosque network, which had sunk deep roots that had spread wide during years of political oppression, provided the popular muscle; it was the force that propelled millions into the streets. But despite fervent and widespread reverence for Ayatollah Ruhollah Khomeini, the new Iran could have taken any number of identities.

Among those who had cast out the shah were communists, nationalists, socialists and others — many of whom envisioned at least some flavor of democracy. Some of these groups were highly organized and well-financed, especially Tudeh, Iran's communist party. These groups had varying ideas about the new Iran, but were united in preferring a secular state.

Ayatollah Khomeini himself was of two minds on the subject: He did not immediately seize power on his triumphant return to Iran from Paris but retreated to the holy city of Qom, appointed a provisional government manned by the secular political leaders who had surrounded him in exile, and established a revolutionary council to write Iran's new constitution.

The idealistic young Iranians who seized the embassy that month and held 52 Americans hostage for more than a year, however, wanted a total Islamic revolution. They faced intense competition on college campuses from Tudeh and other secular groups. Feeling outnumbered, they formed the umbrella group Strengthen the Unity to combine the Islamist students scattered throughout the city into a single force.

In the confusing, violent aftermath of the revolution, there were plots galore. Ahmadinejad feared the influence of Tudeh most of all; he argued that the better embassy to occupy would have been the one belonging to that party's sponsor, the Soviet Union. He lost that debate to those in his group who felt the greater threat was America, the nation that had propped up the shah for more than 25 years.

The embassy seizure worked beyond its plotters' wildest expectations. It was greeted with extravagant enthusiasm throughout the nation. In Tehran itself, hundreds of thousands of happy citizens took to the streets to dance on the Stars and Stripes and burn President Jimmy Carter in effigy. It was a great party of purgation, casting off all remnants of American domination.

Ayatollah Khomeini, whose initial response to the takeover was to order the students chased off the grounds, reconsidered when he heard reports of its popularity. Overnight heroes, the student occupiers quickly produced "evidence" on Iranian TV to substantiate their claim that America had been planning a countercoup.

For years, the United States had used its base in Tehran to coordinate spy operations against the southern Soviet states, so there was plenty of high-level espionage equipment to place before the cameras — coding and decoding equipment, shredders and disintegrators, a plastic-walled "bubble" for holding conversations free of electronic eavesdropping, and the like. All the Americans seized were labeled spies, including Marine guards and secretarial staff. The students had not just occupied the U.S. Embassy, they claimed, they had uncovered and thwarted an evil plot to destroy the revolution and assassinate Khomeini.

The immediate effect was the collapse of the provisional government. A week before the seizure, Prime Minister Mehdi Barzagan and his foreign minister, Ibrahim Yazdi, had met informally with President Carter's national security adviser, Zbigniew Brzezinski, in Algiers to explore new footing for a relationship between the two longtime allies. After the embassy takeover, that meeting, revealed in the press, appeared sinister. When Khomeini sided with the students, and with their claims of an American plot, it was clear that a dangerous season had opened for secular politics. Barzagan and his government stepped down.

Day after day, the student hostage-takers held news conferences broadcast in Iran, and sometimes around the world. While the United States was fixated on the fate of the hostages, a different drama played out in Iran. Using files seized in the embassy, the students smeared secular political leaders with charges of treason and spying.

The Muslim students had reason to fear competition. There remained strong support for a more secular government, and some of the provisional administration figures remained popular. Abolhassan Bani-Sadr, a minister in the collapsed government, was elected president in early 1980. He and Sadegh Ghotzbadeh, the new foreign minister, took on the hostage-takers in their first months in office. They tried in vain to arrange for transfer of the hostages to government custody, and publicly condemned the students, even as the daily embassy news conferences started featuring denouncements of members of their own administration.

But by then it was too late: Bani-Sadr was eventually branded a spy and now lives in exile in Paris; Ghotzbadeh, who secretly met several times with President Carter's chief of staff, Hamilton Jordan, in an effort to end the hostage situation peacefully, was arrested and executed in 1982.

What does all this have to do with today's nuclear standoff? The embassy occupation in 1979 was viewed by most Americans as a challenge to our world authority and a statement by the Iranian revolutionaries that they wanted to take Islamist rebellion beyond Iran's borders; in fact, it was primarily a well-orchestrated confrontation intended to place the mullahs firmly in power.

Today, as Iranian supreme leader Ayatollah Ali Khamenei presides over an increasingly restive, unhappy population, his pit bull, Ahmadinejad, has picked a new fight with the United States. Even many Iranians who oppose the theocracy now favor joining the nuclear club; it adds to national prestige and arguably enhances security. In pursuing nuclear power and defying world opinion, the old revolutionaries are shoring up their stature at home.

And why shouldn't they? It worked before.