VIENNA, June 8 -- Rafael Grossi was unambiguous on Monday about where the International Atomic Energy Agency stands on the most combustible security question in Europe right now. It stands outside the room.

The IAEA director general told reporters that his organisation is not involved in discussions about whether the United States should deploy nuclear weapons in Poland and several Baltic states, and drew a pointed distinction between the agency's civilian mandate and the alliance politics driving those talks. "We are not involved, we are not a nuclear weapon organisation," Grossi said. "These matters are in the realm of the defence policies of these countries."

The remarks amounted to something more than a bureaucratic clarification. T...