I'm sure Hamid Karzai has some problem, but it strikes me as intuitively a bit absurd to hold him personally responsible as being "not up to addressing Afghanistan’s many troubles." It's not, after all, as if Afghanistan has some long record of troubles being well-addressed and everything going smoothly until Karzai showed up. Meanwhile, neither the United States nor the Europeans have done as much as they/we should or even said we would to help out. Shifting the blame onto Karzai is just a low blow.
Matthew Yglesias is a former writer and editor at The Atlantic.