The current "crisis" between the U.S. and Iran has complex and deep roots. While past American "meddling" in Iranian affairs and U.S. support for the Shah's repressive regime still irk many Iranians, most of them also oppose the conservative religious regime that dominates the country.
Surprisingly, despite efforts to brand the Iranian regime as "authoritarian" or even "totalitarian" there's an amazing amount of public dissent, ranging from newspaper and television criticism (usually carefully tailored to focus on obvious abuses). There is also massive resistance to attempts to abolish traditional pre-Islamic practices, such as the annual new year's observances (just completed), which are marked by public bon fires and partying in keeping with a custom that reaches back into the times when Iranians followed the Zoroastrian faith. America and Americans are generally viewed quite favorably by most Iranians, and trendier people open flaunt American cultural icons; Iran was the only Moslem country in which there were spontaneous mass public demonstrations of sympathy for the U.S. following the 911 attacks.
But even many pro-American Iranians are "disappointed" with the U.S. During Operation Enduring Freedom, Iran played an important, if covert, role in the successful American effort to overthrow the Taliban. There were both religious and political reasons for this. The Taliban's ultra-Sunni sectarianism was inherently hostile to Iran's Shiite brand of Islam. Not only was Afghanistan's small Shia minority prosecuted by the Taliban, but the Taliban even attempted to stir up trouble among Iran's Sunni minority.
Iran was one of the main sources of funding for the warlords who were fighting the Taliban during the 1990s. When the U.S. jumped into Afghanistan in late 2001, Iran encouraged its pet warlords to cooperate with American efforts and supported the formation of the Karzai government. Relief supplies were permitted to move across Iranian territory. And, most surprisingly, Iran raised no objections when American aircraft occasionally (or not so occasionally) violated its airspace. At the time, many Iranian leaders apparently believed the effort in Afghanistan would lead to some improvement in ties with the U.S. Instead, Iran found itself included in "The Axis of Evil." This had a major effect on the following elections; political and religious leaders who had been urging a rapprochement with the U.S. were discredited and barred from running for office, which led to a resurgence of ultra-conservatives in the religious leadership, which in turn led to the election of the nearly maniacal Mahmoud Ahmadinejad.
Making matters worse, is the issue of Iran's efforts to develop nuclear power. This actually began under the Shah, and seems to be viewed very favorably by most Iranians, even those staunchly opposed to the regime. The effort by the ultra-conservative leadership to piggy-back a nuclear weapons program on top of the nuclear power program is not so widely supported.
While nuclear arms might bring Iran some prestige, their possession would not necessarily greatly enhance the country's overall power and influence. Indeed, reportedly some Iranian military leaders have argued against acquiring nuclear weapons, on the grounds that they would handicap Iranian strategic flexibility and security. Among their arguments, they cite the probability that, confronted by a nuclear-armed Iran, the Gulf Arab states would be driven even further into the American orbit, and while several other adjacent countries (e.g., Turkey, Pakistan, and Russia, as an ally of the Central Asian "Stans") would probably become much less friendlier than they already are.
Some generals have even argued that nuclear weapons will probably not be of much use against Israel. While being able to annihilate Israel with a couple of bombs might make some arch-conservative religious leaders happy, it would certainly open the country to massive retaliation by Israel, and would lead to the destruction of the Moslem holy places in the country, not to mention a couple of million Brothers-in-Allah. In addition, they are apparently terrified that if Al-Qaeda or some other terrorist group were to employ a nuclear device or even a radiological weapon, Iran would suffer immediate consequences, whether or not it had any ties to the incident. Surprisingly, some important religious leaders are apparently backing these military arguments with the claim that the late Ayatollah Khomeini, leader of the 1979 revolution, issued a fatwa condemning nuclear arms. Despite this, of course, the country is moving forward. Just how "imminent" possibility of an Iranian nuclear weapon is difficult to assess. Nevertheless, despite often hysterical predictions, it seems unlikely to happen within the next couple of years.`
This should leave plenty of room for diplomatic jawing. A great many nations have nuclear power industries. Some - perhaps as many as 25 - are even known to have adopted what is known in some circles as the "Japan Option"; that is, they don't have nuclear weapons, but could get them pretty quickly, a category that includes several surprising candidates, including Sweden, Germany, and many other European Union nations, as well as Switzerland, and, of course, Japan. Russia has been pursuing a diplomatic approach that leaves Iran with a nuclear power capability and controls on weapons development, but the U.S. has so far been holding out for the complete elimination of the country's nuclear research program for any purposes.
The alternative to a diplomatic solution is an attempt to find a "military" one. There aren't too many military options open to the U.S. Large scale air strikes could set back the Iranian program, but would certainly not end it. They would also be greatly resented by the mass of Iranians. Nor would Iran be without retaliatory capability. Iran has apparently been holding back some of the more radical Shia factions in Iraq, and could, in retaliation unleash these against government and U.S. forces in the country, plunging it into further chaos.
March 18, 2006: The U.S. has told Iran that the Iraqi Shia militias being supported by Iran (the Sadr and Badr organizations) are going to get taken apart soon, and Iran is well advised to back off when this happens. Hardliners in the already hard line Iranian government, have been helping Badr, Sadr and smaller groups, in order to keep the atmosphere hostile for the United States in Iraq. This has not been particularly popular in Iraq, because it's obvious that the Americans chased Saddam out of power, and made it possible for Shia to run the country. But to old school Iranian Islamic radicals, hating and hurting the United States is more important than anything else.