I wouldn't say that's a contradiction. It's cynical. Millar believes that the world we live in, and thus the world he writes about in exaggerated form, is a place where the biggest bastard wins; hence, most of his heroes (apart from his lighter works, like his run on Fantastic Four), who are either liberal bastards (The Authority) or parodies of conservatives. The end of Ultimates 2's "Grand Theft America" is a perfect example of the latter; Millar constructs the whole "Ultimates vs. Liberators" as Bush-era interventionist foreign policy vs. the backlash. Now, the backlash consists primarily of regimes even worse than Bush's biggest excesses, but the Bushites win not because of morality, but through shear bloodymindedness. The story ends with Ultimate Cap, who up until that point was basically distilled anachronistic jingoism, learning the lesson that preemptive strikes and government-funded heroes are a bad idea, and they go independent and international.