Is the Iran deal unraveling? Think again.

Are the wheels coming off the Iran deal? Less than a year after Iran, America, and five other world powers inked a comprehensive nuclear accord, a debate over its terms has erupted anew.

In Washington, the braggadocio of a prominent White House aide is fueling Republican accusations that President Obama deliberately deceived the Congress and the country about Iran and the deal. And in Tehran, frustration over the residual impact of American sanctions has prompted increasingly resentful accusations from Iranian leaders that the United States has failed to live up...