Without defending the war in Iraq (afterall what good has it done?) this really is a false equivalence and we probably don't realise how good we have it, and how much worse it could be - namely if some one like UBL was the ruler of the worlds largest superpower how many people would be killed and oppressed.

You may pine for an ideal of no unjust/unfair deaths in the world, but the reality is the number caused is in some way proportional to the power wielded. The assessment of the morality of the US should take this into consideration. That is to say there is an implicit negative opportunity cost (? opportunity benefit) to existing power. This is perhaps the opposite to the way most overly moralising critics view things (if only I had the power to change the world). Afterall perhaps the biggest lesson of Iraq must be that just getting rid of power based on simplistic moralising is not a good idea. Careful what you wish for.

Let's say I do this, and arrive at a verifiable mathematical proof that George W. Bush and Donald Rumsfeld and whomever else aren't as vilified.

What will I have learned?

If I'm a decent human being, what different choices do I make for having learned this?

At the end of the day, all three of these people are horrible, murderous thugs. UBL will of course never have a chance to apologize or make amends. We can hope that Bush and Rumsfeld have life-altering experiences that cause them to dedicate themselves to making their victims whole, but history is somewhat short on these sorts of stories.

The best we can do is to live lives as decent human beings, helping and loving each other and refusing to work for welfare-warfare states and crony capitalists. There's no additional benefit, as far as I can see, to efforts to parse whether some murderers are vilified in proper proportion to their war crimes.

lsd5you has already provided a good response, but in addition to that:

1. Explicitly targeting civilians is generally considered grounds for vilification - it's why we call them "terrorists", and why we have rules of warfare, etc.

2. It's pretty standard to vilify people who are trying to kill you, rather than people who are trying to kill others on your behalf. If you want to take a stance outside of national interests, that's fine, but again it's not unreasonable for Americans to feel more hostile towards Bin Laden than Bush, even if they disagree with the Iraq War and its consequences.

3. In a better world, the Iraq War certainly should have resulting in crimes against humanity charges being brought and tried against perpetrators like Bush, Cheney, and his gang. But the fact that we don't live in that world doesn't change the fact that what Bin Laden did was a bad thing, which justifies vilification.