According to the terms of the Joint Comprehensive Plan of Action (JCPOA), the Islamic Republic is allowed to continue research and development on more advanced nuclear centrifuges. In 2024 it will be able to begin using these, and in 2026 it can enrich as much uranium as it wants, short of levels suitable for making atomic weapons. By 2031, all restrictions will be lifted. The results, writes Ephraim Asculai, are that even without cheating, Iran can gradually abbreviate the amount of time it would require to start producing nuclear weapons:
[I]f Iran abides by the agreement to the letter, by the eighth year, if not before, Iran can have perfected one or more centrifuge models capable of high rates of enrichment. Iran would be in a situation in which it had already prepared the capacity to produce as many centrifuges as it wants and at the rate of production it chooses, even if not actually producing these before the eighth year.
By year ten, Iran’s breakout time will already have been reduced considerably; and by year fifteen Iran is officially permitted to do all it wants, including significant amounts of enrichment to military levels (around 90 percent). The breakout times will then be measured by weeks, not months. . . .
Iran knows how to be patient. There should be little doubt that unless something dramatic changes in the Iranian regime or its policies, it will seek this nuclear capability.
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