Ah ha! I found one that I can weigh in on with some fun little facts...
Iran is evil, as presented to me and a group of other US Army Intelligence Professionals by a senior analyst for the ME Desk in Langley, VA (for those kids that don't do math and can't put 2 & 2 together, that's CIA)...
Iran having nuclear weapons is bad for the west. 1) Nuclear weapons must be strictly guarded and accounted for, the former Soviet Union did a piss-poor job at this and "lost" some of their stockpile, Iran "loosing" just one 5MT nuclear weapon would be beyond bad. 2) Iran has outwardly and loudly supported anti-western and pro-Palestine terrorist organizations (Hezbollah comes to mind, and they fucking HATE us), so it would come as no surprise that a nuke could slip into the hands of one of these groups and next thing you know that lovely area once known as Tel Aviv is wiped off the map (not to mention they could even target DC, NY, LA, etc.). 3) Does no one remember the hostage crisis in the 1980s? 4) Even if they don't intend to weaponize and use nuclear fission technology in a bad way, what if in their all too wonderful abilities (I'm referring to a 2009 incident where their nuclear enrichment program was brought to a screeching halt by a flash drive introduced virus- no one knows who was behind the cyber attack) they somehow manage a colossal fuck up like the USSR did at Chernobyl... well I can tell you none of us would shed too many tears, until the prevailing winds push the fallout to somewhere like Afghanistan and we start ending up with US troops coming down with radiation sickness- perhaps the worse way to die.
Thus, if you look at the logical and sound reasons why Iran should definitely NOT have anything to do with nuclear technology and still ask "Why do we see Iran as evil?" you need your head examined... Iran is a crazy crazy place that is in a constant struggle to deal with being a strict sharia Islamic republic and a modern fast growing society... too bad the moderates are shut up pretty fast by the likes of Wahhabi clerics and hard-line Muzzies.