Gary Samore, Director of Research at the Belfer Center for Science and International Affairs, writes in Time that the emerging nuclear agreement with Iran, while not perfect, buys needed time for the United States and its allies to continue to manage the potential threat of a nuclear Iran. He notes that the agreement will severely restrict any Iranian attempt to build a nuclear weapon through enriching plutonium, as it mandates modification of the Arak Nuclear facility and bans the construction of a nuclear reprocessing facility, which would be necessary for extracting plutonium from used fuel rods. However, the agreement does leave Iran with a much more robust uranium enrichment program, with restrictions for ten years which are steadily eased between fifteen and twenty-five years after the agreement is signed. He suggests that while it may be possible to get a better deal with tougher negotiating tactics, the United States will not be able to keep international consensus pressuring Iran if it rejects the deal after Iran appears to agree to it. He concludes that while this does not solve the problem of the Iranian nuclear program, it gives the United States time to check Iranian regional designs, encourage political change in Iran, and seek other ways to change the regime's calculus about nuclear weapons.