President Obama Answers Iran Deal Questions on Quora

We can either prevent Iran from obtaining a nuclear weapon through diplomacy, or be left with a form of war. Those are the options. As Commander-in-Chief, I have not shied away from using force when necessary, but I cannot in good conscience place the burden of war on our men and women in uniform without testing a diplomatic agreement that achieves a better result. That is the lesson that I hope we’ve learned from more than a decade of war and the weight of its consequences. Diplomacy is not easy, but it is a better choice.

So let me be clear: This agreement is not based on trust. It’s based exclusively on unprecedented verification. Never before has a nuclear non-proliferation agreement included such a robust and far-reaching monitoring and transparency regime. Under this agreement, Iran is prohibited from ever pursuing a nuclear weapon — and we will be in the strongest position ever to make sure that Iran follows through.

Under this agreement, Iran is never allowed to build a nuclear weapon — period. Every single pathway Iran could use is effectively blocked by this deal. Here’s how: It takes either enriched uranium or plutonium to build a nuclear weapon. The only site where Iran can create weapons-grade plutonium is at its Arak reactor. Under this deal, the core of the Arak reactor will be pulled out, filled with concrete, and replaced with one that will not produce weapons-grade plutonium. Furthermore, the spent fuel from that reactor will be shipped out of the country and Iran will not build any new heavy-water reactors for at least 15 years.