People are asking how certain President Obama is that the tall old Arab shot last night in Abbottabad was in fact al Qaeda's Osama bin Laden? Answer: almost exactly as certain as President Bush was about the existence of weapons of mass destruction in Saddam's Iraq.
In other words, both believed they were right when they made the claims. Both had great reason to want the intel to be correct.
In hindsight, Bush was proved to be wrong. For the nation's sake, let's hope Obama doesn't have the same bad luck.
