Larry Kaplow

President Trump's Iran address creates uncertainty about the long-term survival of the two-year-old nuclear deal. It opens the door to Congress to find ways out of it, even as he threatened — yet again — to use his power as president to break the deal himself.

But for now, the deal stands — with the administration itself acknowledging it's better to have it than to break it.

In 2015, world powers agreed to give Iran relief from some economic sanctions in return for inspections and limits on its nuclear program. Since the nuclear deal — formally known as the Joint Comprehensive Plan of Action — took effect in January 2016, Iran has allowed inspections and is seeing some economic payoff.