"Iran is run by a nasty regime that destabilizes an important part of the world, [more than, say, Israel?] frustrates American and Western interests, [which are what exactly?] and causes problems for allies like Israel. [see 1 and 2] But let's get some perspective."

Why quibble? Fareed Zakaria lays it out clearly enough that even an idiot should understand. A link from Laura Rozen