Rothbard understands government intervention as a distortion of the natural economic order, whereby all men are free to contract with all others. But Rothbard's personal views are not manifested in Power and Market by way of partisan or lopsided political rhetoric. Rather, his analysis of the effects of economic intervention is strictly academic and consistent with the charge of professional economists to remain wertfrei, or value neutral, while elucidating economic truth. Where Rothbard does criticize impure laissez-faireists and proponents of government intervention, it is not without a strong defense of his own views and a careful dissection of exactly where interventionist policies go awry. His opponents are thus painted as wrong by implication of his economic analysis and not by his assumptions about their unspoken motives or their being of a different intellectual background or political persuasion.
I have drawn heavily upon Rothbard's work in Power and Market for the sections in my Foundations of Economics that deal with economic policy. I recommend both Freiling's review and the book itself. I also encourage you to take a gander at the economics blog to which he contributes, Hans Economics.