To replace neoconservative democracy promotion by force, Obama seems to be proposing a different kind of crusade. He and his advisers seem to believe that American foreign policy can deliver the human race from indignity and want. Even if their strategy for achieving this goal doesn't rely on military force, such an expansive view of the capabilities of U.S. foreign policy is dangerously unrealistic. It seems particularly overly ambitious in light of the growing evidence about what traditional forms of development aid have actually accomplished. (Not to mention that Obama's agenda seems too hostile to a form of global development and economic uplift that often proves rather more effective than aid: trade.)
I don't really think this holds water. The rhetoric of American foreignpolicymaking has always been suffused with grand -- some would say grandiose -- aspirations and professions of lofty ideals. And yet the actual substance of policymaking has differed enormously over the years, decades, and centuries. That's because methods -- what's dismissed here as "their strategy for achieving this goal" -- are essentially the entire ballgame. Practical American politicians will always commit themselves to a set of basically similar highest-order goals of spreading wonderfulness throughout time and space. Even in our "do not seek out monsters to destroy" phases we're supposed to be a model the rest of the world will emulate.
Are these aspirations "dangerously unrealistic" and "overly ambitious?" I think it depends on what you mean. To say that the short-run policy objective of the United States is to wage war on tyranny is dangerous and unrealistic. But to say that the long-run goal of the United States is to do what we can to foster the conditions of international peace and prosperity that are most conducive to the spread of liberalism and democracy seems eminently sensible.