The United States and Israel have launched a vociferous global campaign to justify an attack on the Iranian nuclear facilities. Israel paints the Iranian nuclear program as an existential threat to itself whereas the United States characterizes the Iranian program as a peril to international peace and security. Most Western European states and some Middle Eastern states, including Saudi Arabia, view the Iranian quest for nuclear energy with suspicion and alarm. Russia and China, the permanent members of the U.N. Security Council, and numerous Muslim and non-Muslim states in Asia, Africa and, Latin America, even when they are unsure about Iran's intentions, oppose an armed attack on Iran.
As a State Party to the Nuclear Non-Proliferation Treaty (NPT), Iran claims a lawful right to develop nuclear energy, just as scores of States Parties including the United States mobilize such a right to develop nuclear energy. The Iranian leaders deny, in an unambiguous language, that they intend to develop nuclear weapons. Ayatollah Khomeini, the founder of the 1979 Iranian Revolution, had opined that Islamic law prohibits the possession of nuclear weapons. Consistent with Iranian assurances, U.S. intelligence agencies believe that Iran has not made a decision to manufacture nuclear weapons.
Rejecting Iranian statements as lies, Israel, more than the United States, is planning an armed attack against Iranian nuclear plants and the associated command and control headquarters. The irony is that Israel itself possesses hundreds of nuclear weapons it has built with the covert assistance of the United States. As a self-appointed sheriff of the Middle East, Israel refuses to allow any other state in the neighborhood to develop nuclear energy. All by itself, Israel unlawfully destroyed the nuclear energy plants in Iraq and Syria. Israeli intelligence agencies assassinate Iranian scientists and nuclear engineers, an illegal course of action that no other state undertakes or endorses. The United States would commit a great wrong, argues Israel's Prime Minister, if the United States does not soon start a war with Iran.
There are two distinct reasons why an armed attack on Iran is illegal under international law, whether the attacker is Israel or the United States.
First, a violation of the NPT does not justify an armed attack. The NPT carries no war clauses for its violations. Suppose that Iran is indeed in violation of the NPT as it refuses to fully submit its nuclear facilities to satisfactory inspection by the International Atomic Energy Agency (IAEA). However, a dispute over the logistics of inspection with the IAEA does not furnish a sufficient basis in international law for any state, including the United States, to launch an armed attack against the State Party. Israel, which has not even signed the NPT, cannot invoke the failed IAEA inspections for justifying an armed attack on Iran, a founding member of the NPT. International law knows no rule under which a state that refuses to sign a treaty turns around to enforce the same treaty, by all means necessary, against a founding member of the treaty. To preempt any such adventures, the NPT Preamble specifically prohibits "the threat or use of force against the territorial integrity or political independence of any State."
Second, the U.N. Charter outlaws war in the following guiding principle: "All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state." As States Parties to the U.N. Charter, Israel and the United States violate this principle when they threaten an armed attack against Iran, again a founding member of the Charter. Israel has not yet claimed the right to self-defense under Article 51 of the Charter. However, any such claim would be dubious. There is no credible evidence that Iran is preparing an armed attack against Israel or the United States, triggering the right to self-defense. Most important, the Security Council is well aware of the Iranian problem. The efforts to persuade the Security Council to impose economic sanctions on Iran have failed. If the Security Council is opposed even to economic sanctions, it is unlikely to authorize the use of force against Iran.
Israel and the United States may petition the Security Council under Chapter VII of the U.N. Charter for the use of force to deter Iran from manufacturing nuclear weapons. Bypassing the Security Council, any armed attack on Iran will be akin to the unlawful invasion of Iraq. In that case, the attack will have zero legitimacy under international law.