If the USA had bombed Afghanistan with dollar bills instead of explosives, they would have caused the collapse of the Taliban - regimes like that don't survive too well with material prosperity. The war would have been cheaper, too.

The Taliban would have been replaced by another bunch of thugs - probably the same ones there now. That's the way Afghanistan has been for x centuries. At least, though, they'd have more assets, and they would have fewer dead to bury.

Having failed dismally to catch Osama by bombing the daylights out of the Afghans, the USA must now consider alternatives. It's just too horrible to contemplate attacking Saudi Arabia (where I'll bet Osama is right now) because they have too many oil wells with American connections. The alternative is to create a diversion with good old Saddam.

Note that Saddam isn't really doing anything now that he hasn't been doing for the last ten years - he just happens to be convenient.