There are two issues here, and some people are confusing them.
There's the issue of whether AIG ought to have paid bonuses to these people.
I've spent 25 years now in the cubicle land of corporate America. I've seen bosses at all levels come and go, from CEOs to my immediate managers, and everyone in between. They have left because they were fired, because they got better jobs somewhere else, because they retired, and because they died. My job hardly ever changed.
The point of this anecdotal evidence is that I think executives are highly overrated. Sure, they are important, but they can be replaced, and for that reason I think they are highly overcompensated. I think for every guy who won't bother showing up to work unless he is paid two million bucks, there's a guy out there with more ambition, energy, and talent, willing and able to do the same job for a mere million. I think the only reason the megasalaries are paid is pure power. The execs control the board, and have the power to make sure the "executive compensation committee" determines that the current crowd of execs is severely underpaid unless they get an extra million, and that the company certainly couldn't do without them. Of course, for this service of attending a few meetings a year, and keeping a very well connected Rolodex, the board members themselves are compensated with a few hundred thousand bucks. In other words, I don't think the bonuses were money well spent.
However....that's not the issue. There is something very frightening about the government walking in and choosing who gets to keep their money. I have no problem with the new government pseudo-owners paying less compensation to exectives who are in charge of failed firms taking bailout money. Seems perfectly reasonable. To use the tax code to correct problems like that, though, seems like a very, very bad idea.