True, but Bush being an idiot does play a big part in this, and he isn't getting any closer to improving relations, more like making them worse...
Well, that was Al-Qaeda, from Saudi Arabia, not the Iranians. Keep in mind that the Sunni and Shite regimes are also enemies to each other; though they both hate the west that doesn't mean that they are allies. Iran, which is predominately Shia, is very unlikely to help Al Qaeda, and Hizbollah and Syria (Iran's allies) are much more focused on Israel then on the U.S. or Europe.