Yglesias isn’t the only liberal with a large ideological investment in the idea of a “rules-based international system.” Some such notion is behind all the talk about a foreign policy of “engagement” coming out of the Obama administration. As far as I can see, however, it's far too formulaic an idea to bear the normative weight that liberals are putting on it.“Post-Iraq soul searching combined with the emergence of a presidential candidate untainted by support for the invasion has bolstered the development of a clearer idea of the liberal goal in international affairs, what the Obama National Security Strategy calls "a rules-based international system that can advance our own interests by serving mutual interests. Several years earlier, the Princeton Project on National Security came up with the more elegant "A World of Liberty Under Law." The idea in either case is that instead of struggling fruitlessly for perpetual dominance of the anarchic international realm, America liberals should strive to tame it by helping build a set of rules and institutions that can accommodate the legitimate interests of all nations."
Not even swashbuckling neo-conservatives deny that, whenever possible, it’s best to promote core national security objectives by invoking international law and acting through international institutions. The idea of promoting a “New World Order” in the wake of the cold war was introduced into political discourse, after all, when Dick Cheney’s Defense Department was running the Gulf War. Granted, that was a matter of undoing aggression by one sovereign state against another, but even George W. Bush spent the better part of six months trying to win the consent of the UN Security Council for his campaign against Saddam before pressing ahead on his own. By the same token, if pressed, the primmest liberal internationalist will concede that it’s permissible for sovereign states to act unilaterally, even in defiance of the UN Security Council, when in their own best judgment acting unilaterally is necessary to secure a sufficiently urgent national security objective.
As far as I can tell, nobody thinks that the United States, or any other nation-state, has an obligation to submit to the determinations of international institutions akin to the political obligation American citizens incur to each other to submit to legitimate governmental decisions. The disagreements between liberals and conservatives in this connection come down to conflicting prudential judgments about how advisable it is to forego immediate advantages procurable through unilateral action in the interest of promoting rule-governed cooperation among sovereign states. Generally speaking, liberals are willing to forego more unilateralism because they think, correctly in my view, that conservatives tend to over-estimate unilateralism's immediate benefits and under-estimate the remote benefits of strengthening the regime of international law. Yet such judgments will always invite disagreement, not only between liberals and conservatives but within the liberal and conservative communities, because they have to be made on a case-by-case basis under conditions of extreme uncertainty. Foundational foreign policy principles aren't much help.
The normative triviality of the idea of a "rules-based international system" is revealed when Yglesias tries to turn it against Obama’s Af-Pak policy:
Yglesias never explains how current Af-Pak policy undermines sound liberal foreign policy principles. To do so, he'd have to establish that Obama's wrong to portray both the counterinsurgency campaign in Afghanistan and the predator drone strikes in Pakistan as permissible acts of national self-defense under international law. That doesn’t make either policy wise, of course, but it arguably makes them perfectly consistent with anybody’s idea of a sustainable “rules-based international order.”“Realistically, however, the Obama administration's quiet efforts to turn [a “rules-based world order] into a reality -- from the New START treaty to defusing the pointless Latin American Cold War -- are overshadowed by the reality of military action in Afghanistan and Pakistan. These operations don't seem to be going very well and don't fit within this new framework. Semi-secret predator drone strikes conducting an officially nonexistent undeclared war in Pakistan, to name one example, fit awkwardly with the idea of a rule-governed world. As a result, hawk-versus-dove tensions are once again resurfacing, as seen in the refusal of many House Democrats to vote for Afghanistan War appropriations and Press Secretary Robert Gibbs' recent outburst about how progressives won't be happy until the whole Pentagon is eliminated.”