As it approaches its first 100 days in the White House, the Trump administration has put Iran "on notice" and imposed new sanctions — and now it is launching a review of a historic accord with Tehran that limits its nuclear program.
That review marks the most strident step toward President Donald Trump's campaign trail threats to pull out of the deal. It will assess whether doing so is in the national interest of the United States in light of a range of American grievances with Iran.
However, those grievances were never meant to be addressed by the nuclear negotiations. Any attempt to scuttle the deal for reasons not spelled out in the accord would likely be viewed as illegitimate by the nations that hammered it out and could potentially spark diplomatic and trade disputes with some of America's closest partners.