Pressed this week to define President Trump’s goals in escalating military and economic pressure on Iran, one of his top foreign policy aides ticked through a familiar list: End the country’s support for terrorism, stop its missile launches and then, most importantly, keep Iran more than a year away from the capability to build a nuclear weapon. The United States would insist on “zero enrichment for Iran,” Brian H. Hook, the State Department’s special envoy for Iran, told a small group of reporters. That would assure Tehran could produce no new nuclear material, and thus never get closer to building a weapon than it is now. It was a telling moment in a strange, circular week of mutual threats and missed signals between bitter adversaries. Designing an agreement that would assure it would take Iran a year or more to “break out” and make the fuel […]