The question of whether military force should be used to prevent, or at least delay, Iran from building a nuclear weapon is again on the front pages. Both President Obama and Mitt Romney have said they would consider a military strike against Iran. According to media reports, the necessary planning has been completed, and military options are “fully available.”
But there has been almost no discussion of whether an attack by the United States would be legal under domestic and international law. This should be a priority. Law is important, especially in issues of war and peace.
The United States has long maintained the right, under international law, to take unilateral, preemptive action to prevent an attack on the nation. We have, for example, never agreed to a “no-first-use” policy for our nuclear weapons.
However, presidents who have authorized military actions have generally tried to demonstrate that they are permissible under international law. Under the U.N. Charter, member states may use force against another country only if authorized by the U.N. Security Council or in self-defense against an “armed attack” (which most international lawyers agree includes the threat of such an attack). President George W. Bush relied on the right to self-defense and a Security Council resolution to invade Afghanistan after the Sept. 11 attacks. He cited Security Council resolutions dating from 1990 as authority to use force against Iraq in 2003. President Obama has relied on a self-defense rationale (or the consent of the country involved) to conduct drone strikes in Pakistan, Somalia and Yemen. The Security Council authorized the use of force against Libya in 2011.