The killing of Iran’s top nuclear scientist is likely to impede the country’s military ambitions. Its real purpose may have been to prevent the president-elect from resuming diplomacy with Tehran.

The State Department inspector general fired by President Trump on Friday was in the final stages of an investigation into whether the administration had unlawfully declared an “emergency” last year to allow the resumption of weapons sales to Saudi Arabia and the United Arab Emirates for their air war in Yemen.

The secretary of state is preparing an argument that the U.S. remains a participant in the Obama-era nuclear deal, with the goal of extending an arms embargo or destroying the accord.

The Trump administration has begun to put a price tag on its growing arms race with Russia and China, and the early numbers indicate that restoring nuclear weapons to a central role in American military strategy will cost tens of billions of dollars over the next decade.