Will Wilkinson believes that our a priori politics determine our philosophical beliefs:
It seems to me that most of our high-level political concepts like "freedom" or "equality" are tailored and tweaked to justify the kind of political regime we already tend to favor. If you are offended by taxation, you'll settle on a conception of liberty according to which taxation is a violation. If you think a relatively high level of taxation is necessary to give people what you think they ought to get, you'll settle on a conception of liberty according to which taxation is not a violation, but not giving people what you think they ought to get is. That's why abstract political philosophy is so often futile. It's probably more useful to start out arguing over regime types in the first place, since mostly what we do is choose our favorite regime type and then reason backwards to conceptions of liberty, equality, and so forth that justify our pick.