Powell is entitled to his opinion. Powell would never do or say anything that would hurt this country. He spent too many years defending it. I respect Powell's opinion.
Like Brent Snowcroft, Powell's allegiance was to Bush the Elder. Both have gone out of their way to sabotage W since the Iraq War was launched. Powell is ticked off that he doesn't go down in history as the great peacemaker...and he wants to ensure that Condi doesn't eclipse him as SoS.