So will the political struggle, which is on two different levels. One is between the two factions of the 1978-79 revolution — one led by Ayatollah Khamenei, the other by Mr. Rafsanjani, a cunning and controversial figure.

There certainly is ideology and theology in the mix, although some of the “acrimony” is analogous to the late Wallace Stanley Sayre’s observation that academic politics is so bitter because “so little is at stake.”

Here’s where understanding politics, Chicago style, comes in: it’s about survival. If Mr. Ahmadinejad loses, Mr. Rafsanjani is more empowered. One of Mr. Rafsanjani’s posts is as head of the Assembly of Experts, whose primary function is to choose, or replace, the supreme leader.

If Mr. Rafsanjani — who was attacked for corruption in this election even though he wasn’t on the ballot — loses, he may be in peril.

The second struggle is generational. Both sides invoke the slogans and tactics of the campaign used to overthrow the hated shah. Some three-quarters of Iranians were born in the last 30 years and have experienced none of those moments.

All of which makes the American debate over whether Mr. Obama has been tough enough seem sophomoric. The White House claim that the president has been consistent is also ridiculous. He has hardened his position both as a response to political pressure, from some Democrats as well as Republicans, and as circumstances got worse after the June 12 election.

Critics, led by Senator John McCain and some neoconservatives, charge that a stronger American response would hearten the freedom-loving forces in Iran and hasten change. That simply isn’t credible, most experts say. Moreover, if the United States encourages protests and they are violently put down, what does the U.S. government then do? Use force in another Muslim land?