Do you consider Krugman a voice of dissent though? In my opinion he chimes in once the issue is already "safe" and rarely says anything that would endanger his status as a columnist or his relationships with powerful people.

I would only go as far as to say that Krugman is a dissenter from the prevailing line of economic thought in the United States and Europe. He's useful precisely because the prevailing thought crippled our economy and has little success in repairing it.

I can't really speak to his relationship with powerful people.