I'm generally not in favor of it, although there are a few rare cases where I can see it being arguably warranted (the Nuremberg trials and Saddam Hussein being two examples). I think life without parole is ideal for most crimes.
I wouldn't necessarily mind the death penalty for war crimes either but I think that the ICC solution is better. I also think that getting executed can make you a martyr in the eyes of your political fans whereas rotting in prison is not so glorious.
Let's also not ignore the implications of 'death penalty for war criminals': If the Nuremberg laws were applied, then every post-war American president would have been hanged.
I am not a fan of Chomsky but here he is correct.