You want to know where to find the silver lining on eight years of Bush jr? This will be the real test on whether the American public have learned anything at all.
They've had a government that has committed all the atrocities normally associated with the kind of tinpot dictatorships that they're so proud of being better than. A leader who waged war with a foreign country and spent a trillion dollars of their money fighting it, even after it had been revealed to all and sundry that the reasons given (weapons of mass destruction) were bogus. A leader who has clamped down on dissent to unprecedented levels and set up a Department of Homeland Security in response to a disaster that he could have averted - that he was specifically warned about, an attack on American soil.
A leader who diverted resources to a loser war and handled things so deplorably that New Orleans suffered more than they needed to, by a wide margin.
Kill crazy imbeciles normally get locked up.
They don't get to hand over millions of dollars of other people's money to their chum's old company and they don't get to sit back and order the killing without repercussion.
For every Idi Amin who lives out his miserable life in exile, there are those tyrants who are brought to rough justice: Caeucescu's being shot like a dog by a populace who had had enough, Saddam's hanging. One can be sure, though, that no American leader, no matter how corrupt or how terrible, will ever suffer the same.
The good ones get assassinated and the bad ones live on. If you were a Christian you could ruefully note that it is still the Devil's time when Nixon and Kissinger die of old age. (Not that I want to see anyone getting shot - a trial for war crimes would be good. Then maybe they could stack Bush, Cheney, Rumsfeld et al naked in a holding cell with an unmuzzled guard dog snarling in their face. It's only fair.)
Congress have utterly failed to reign Bush jr in any kind of meaningful way. He makes Reagan's record one trillion dollar budget in 1987 appear modest when he doubles that in fifteen years and proposes a three trillion dollar budget this year. Even THE superpower can't sustain that kind of rampant spending. A responsible and sensible administration would be looking at ways of decreasing the deficit.
For all that abuse and so much more - environmental bastardry not being the least - we didn't even get a Ronnie joke or a Nixon diplomatic bridgebuilding; it is possible that we will never again be able to design a whole desk calendar full of Presidential gaffes. You couldn't write satire better than Bush's accidental lamebrained pronouncements. He really is a fuckwit.
So, in conclusion, if America can see what the worst has to offer, maybe they will learn from their mistake and be more careful next time.