As a Muslim and a student of international affairs, I take extreme offense to this. The Qur'an says no such thing. It certainly doesn't say that about Christians; Christians and Jews are People of the Book and not infidels in the slightest. In the society prescribed by the Prophet, Christians and Jews are to be protected and their religious freedom guaranteed. Granted, there are passages of the Qur'an that might give you the wrong idea. However, Islamic scholars are
very divided about what those passages are supposed to mean, as they were revealed during the Muslims' war against the pagan Quraish tribe of Mecca (who were trying to exterminate the Muslims at the time). "Holy war" is a very limited concept in both in orthodox Sunni and orthodox Shia Islam; it may only be waged defensively, in direct response to a physical attack on Muslim lands. Once the invaders are kicked out, the war theoretically should end; however, rulers have historically abused the rules to their advantage.
Newer conceptions of holy war in Islam exist, but they are accepted only by certain movements on the radical fringes of Islamism. Furthermore, the peak acceptance of aggressive holy war in Islam occurred between about 1955 and 1990; since then, most people who once held to an aggressive view of holy war (the lesser
jihad) got tired of it, and changed gears to more conventional political action (protests, elections, etc.).
Additionally, Saddam Hussein was not a very committed Muslim. He placed Arab identity ahead of Muslim identity; his regime was eminently secular. Baghdad in the '70s and '80s was a very Westernized place (rather like Tehran in the '60s and '70s), with bars at every corner and not a single headscarf in sight. On the occasions that Saddam used Islamic rhetoric, he usually directed it against the Shiite Iranians (whom he fought for eight years, please recall) until late in his reign, when he started directing it at the West in a last-ditch effort to stay in power (it didn't work). Beyond that, Saddam=/=Iran. Saddam was a madman. It might be fair to say that Ahmedinejad is crazy, too, but he wouldn't have his finger on the nuclear trigger. That would be Supreme Leader Khamenei, a supremely rational thinker.
Iran's foreign policy has thus far proven to be
very rational, almost ridiculously so. Whenever Ahmedinejad or somebody else goes on a rant about the West, you can be sure that what they're actually doing is trying to shore up support back home. Iranians are an incredibly proud people, and don't like being anybody's





. They remember when the CIA overthrew the democratically-elected Prime Minister [wiki]Mohammad Mosaddegh[/wiki] in 1953. The Iranian Revolution ('79) was a delayed reaction to that; Iranians overthrew the Shah, who was an American puppet, and put in a regime that would not be anybody's puppet.
Iran is building nukes because it wants to show it isn't under anyone's control. One of the few things that the Iranian government and the protesters out on the street (you know, the ones in green calling for democracy and getting slaughtered by the police) agree on whole-heartedly is that Iran deserves the right to a nuke. Strategically, Iran could use a nuke for several reasons. First, it balances out Israel (which has about 200 bombs), which is the other major regional player (besides Turkey, which mostly likes to stay out of things). Second, it's a bargaining chip; there's so much that Iran wants out of the West that it probably could pull if it developed the capacity to build the Bomb. The folks in Tehran are playing a long game: in the long run, they want to be the local Big Dogs in the Persian Gulf. It is quite possible we could do that if we wrangle things properly.
Attacking Iran--in any way, shape or form--is a mistake. A conventional attack would simply rally Iranians behind the government (remember that pride thing?) and a nuclear attack would be overkill and rally Iranians behind their government (or, if that government were completely destroyed, rally them all against the United States).