Iran has until the end of this month for a final response to the UN Security Council's incentive package for halting the enrichment of uranium that could lead to building a nuclear bomb. Today, Iran met its own deadline, proposing what's described in Tehran as "a new formula," which has not as yet been released to the public. At the United Nations, where the US and other Security Council members are studying the response, US Ambassador John Bolton called the move "a significant moment." Nevertheless, nobody thinks Tehran will stop enriching uranium. If it refuses, can the UN agree on punishment for Iran's suspected progress in building a nuclear bomb? The available options might hurt Council members as much as they hurt Iran. Is military action still "on the table?" What are the political stakes inside Iran?