This does not imply a red line authorizing any country to go to war. However respectfully the views of friends are considered, the ultimate decision over peace or war must remain in the hands of the president. Why negotiate with a country of such demonstrated hostility and evasiveness? Precisely because the situation is so fraught. Diplomacy may reach an acceptable agreed outcome. Or its failure will mobilize the American people and the world. It will clarify either the causes of an escalating crisis, up to the level of military pressure, or ultimate acquiescence in an Iranian nuclear program. Either outcome will require a willingness to see it through to its ultimate implications. We cannot afford another strategic disaster.

To the extent that Iran shows willingness to conduct itself as a nation-state, rather than a revolutionary religious cause, and accepts enforceable verification, elements of Iranian security concerns should be taken seriously, including gradual easing of sanctions as strict limits on enrichment are implemented and enforced. But time will be urgent. Tehran must be made to understand that the alternative to an agreement is not simply a further period of negotiation and that using negotiations to gain time will have grave consequences. A creative diplomacy, allied to a determined strategy, may still be able to prevent a crisis provided the United States plays a decisive role in defining permissible outcomes.