[I]t will reduce the risk of Iran getting a bomb better than any of the realistic alternatives. Iran has agreed to physical limits on its ability to produce weapons-grade materials that will assure a break-out timeline of roughly a year for the next 10 years, as well as additional restraints and verification measures to monitor compliance and detect cheating. If the U.S. rejects the deal and returns to sanctions, Iran is certain to return to what it was doing before the interim agreement: installing additional centrifuges, enriching uranium, increasing its stockpile of enriched material, developing more advanced centrifuges, and completing the Arak heavy water reactor. The agreement does not solve the problem, but it reduces the risk for now and buys substantial time to resolve the threat in the future.