The history of Iran is a continuum of conflict. As another storm brewed in the desert, James Truman journeyed through an ancient land where little is as it appears and whose people, despite decades of official anti-Americanism, are largely welcoming and even fiercely polite

Driving into Tehran from the ring of hills that encloses it, you descend slowly through the layers of smoke, smog, soot, dust, and floating debris that enshroud the city. It's an ominous welcome, but not without an eerie enchantment. In the late-afternoon light, as the high-desert sun begins to soften, you can picture a descent into a valley filled with the smoke of a thousand slow-burning brushfires. Or, in a more Iranian image, as an approach to the ruins of a still-smoldering battlefield.

Tehran, the modern capital of Iran, has the feeling of a city under siege. Overpopulated and underserviced, it exists somewhere just a little shy of chaos. Officially, the population is eight million, but most estimates start at twelve. Since 1979, when the Islamic Revolution, under the leadership of Ayatollah Khomenei, drew together the disenfranchised and the rural poor to overthrow the shah, the capital has been flooded with settlers from the provinces at a rate of several hundred thousand a year. Concurrently, Iran has undergone a population explosion: Khomenei had urged his followers to multiply, which they did so successfully that more than half the country's inhabitants are now under the age of twenty-five. This statistic is relished, and manipulated, by both sides of Iran's postrevolutionary divide: The religious hardliners—the mullahs—see a generation educated in the revolution's agenda. The reformers foresee the revolution's collapse amid soaring unemployment and a hopelessly overextended infrastructure.

The dance of power between reformers and hardliners is Iran's central (and openly debated) drama, played out in the governmental stalemate between the elected reformist president, Mohammad Khatami, and the supreme leader, Ayatollah Khamenei, Khomenei's successor (it's less confusing when spoken: Kho-ME-nei emphasizes the second syllable, Kha-me-NEI the last). I hadn't been in the country an hour before the nuances of the power struggle became apparent. Checking into Tehran's Laleh Hotel—formerly the Intercontinental—I was interested to note the absence of the giant lobby banner that the guidebooks had warned about, the one declaiming down with the usa in English and Farsi. It had been hung shortly after the revolution, when all foreign-owned hotels were nationalized. I'd read that Khatami, mindful of his country's vanished tourism industry, had tried several times in the past six years to have it removed. Each time the conservatives had blocked him. So what had happened? Asking around, I learned that the president's people had recently scored a neat end run: They'd had the banner taken down to be cleaned, and subsequently managed to lose it.

I'd traveled to Iran last fall with the thought of overlooking the country's politics and focusing on its history and natural beauty. This thought quickly disappeared, not least because Tehran itself is short on both history and beauty. A few hours in the National Museum of Iran began to illuminate the conjunction of politics and culture that has forever shaped Persian history. (Persia was renamed Iran in 1935.) The museum is divided into pre- and post-Islamic collections, honoring the convulsive event of the seventh-century Arab conquest. But the larger story is of serial convulsions, and it begins to look like a miracle: how a barren desert sandbar was sequentially overthrown and ravaged by murderous invaders and rescued by saviors who revealed themselves as tyrants and by tyrants who turned out to be saviors, and how, through it all, a culture took root and continuously flourished, transforming everything it touched, even that which had come to annihilate it. The museum elegantly lays out this history of multiple renaissances, with the story ending in the decadence and lethargy of the late-eighteenth-century Qajar dynasty, when Persia, never colonized but widely exploited, fell off the political map. In their attempts to bring it back, the two twentieth-century shahs, Reza and Mohammad, would usher in Westernization, creating the bogeyman that eventually led to the Islamic Revolution.