On Friday, Gen. Wesley Clark penned an Op-Ed in the Washington Post arguing against U.S. intervention in Libya. While I disagree with his conclusion—as I noted here, I advocate for covert military support for the Libyan rebels as an initial matter—Gen. Clark raises some excellent points. Among them:
In Libya, Gaddafi has used and supported terrorism, murdered Americans and repressed his people for 40 years. The American public may want to see him go. But his current actions aren't an attack on the United States or any other country. On what [legal] basis would we seek congressional support and international authorization to intervene in a civil war? Do we have the endorsement of the Arab League? A U.N. Security Council resolution?
International law evolves through custom and through treaties. Custom is defined by state practice—the actions of one or more states in a particular situation, the justifications put forward by those states, and the reactions of the rest of the international community. In Libya, instituting a unilateral (or even a multilateral) No-Fly Zone without a U.N. Security Council Resolution—or at least a determination by NATO that Qaddafi is threatening the alliance—risks rolling back 80 years of international law prohibiting aggression.
Once, war as a political tool was common place. The power to make war at will was seen as the prerogative of every sovereign. (In fact, what differentiated fully- and quasi-sovereign states was the lawful ability of the one to make war in contrast to the other.) That era faded with the signing of Kellogg-Briand Treaty in 1928. The end of the lawfulness of aggressive war was confirmed by the Nuremburg Tribunals following World War II. And, since then, states that have taken offensive action against other states have sought to justify that action almost universally on some other legal basis—general self-defense but sometimes protection of nationals or humanitarian intervention—acknowledging, implicitly, that to engage in offensive war would be illegal.
The problem with imposing a No-Fly Zone over Libya without U.N. sanction is that doing so is certainly an act of aggressive warfare. What else could it be with French recognition for the Libyan rebels, threats from the United States, and demands from other Western states that Qaddafi must leave? Clearly, the West has decided on a political course of action—the removal of Qaddafi—and, by imposing a No-Fly Zone, seeks to effect that course of action.
Worse, an unsanctioned No-Fly Zone would be an act of aggressive warfare widely accepted if not praised by the international community. As such, it would serve as dangerous precedent to any state that might find it convenient to wage war against a neighbor to settle a border dispute, accumulate more land and resources, or merely distract its own populace from troubles at home. Notwithstanding Kellogg-Briand, the U.N. Charter, or the Rome Statute, this customary restoration of lawful aggressive warfare may well undercut the modern international order, legal and otherwise.