the un can't have stood aside at rwanda. the countries in the un stood aside with rwanda. that includes the us.
iraq had two main goals after th first gulf war. to keep power and not be bombed and invaded. to appear powerful a nice few nukes will do that. but not allowed them. so what you can do is appear like you have them while showing that you have destroyed them. their neighbours aren't going to invde becausr they think they have weapons while the un is content because it has seen what it needs to.
alleged means the us claims it and iran denies it and there is no conrete proof to prove it.
on the contrary to feeding and defending the world many world argue you starve, control and imperialise the world and only defending and feeding when it sees fit.
9-11 was a concequence of american actions. 9-11 didn't happen because a few got bored one morning and there was no good tv on and they fancied a good chuckle. they choose one country, one set of buildings with one aim and one motive.