Precautionary measures have not been sufficiently applied to preventing against the risks of nuclear proliferation. Iran has repeatedly crossed red lines regarding its nuclear program with impunity. The best way to prevent the Iranian nuclear crisis from escalating would be for the UN Security Council (UNSC) to adopt a resolution under Chapter VII of the UN Charter deciding that if Iran were to produce high enriched uranium, to separate plutonium, or to notify its withdrawal from the Nuclear Non-Proliferation Treaty (NPT), a number of strong and well-defined sanctions would automatically be implemented without requiring a further UNSC resolution. Although there is no precedent for such a preventive UNSC resolution, it should be more effective in making clear to Iran the negative consequences of its actions than any post facto curative measure.