Because he made a fool of you
Why do neocons like John McCain and John Bolton hate Mohamed El-Baradei? It's very simple; he made liars and fools out of them when he warned them that Saddam Hussein didn't have 'weapons of mass destruction' and they stupidly, and tragically, attacked Iraq and costs us 4,500 young American lives and $2 trillion for absolutely nothing.
If I was John McCain or some other ignorant neocon dumbass who ignored El-Baradei when he was so right and you were such a fuck-up that costs our country so much, I wouldn't want him around either.
