The black S.U.V. carrying Prime Minister Benjamin Netanyahu arrived at the White House just before 11 a.m. on Feb. 11. The Israeli leader, who had been pressing for months for the United States to agree to a major assault on Iran, was whisked inside with little ceremony, out of view of reporters, primed for one of the most high-stakes moments in his long career.

U.S. and Israeli officials gathered first in the Cabinet Room, adjacent to the Oval Office. Then Mr. Netanyahu headed downstairs for the main event: a highly classified presentation on Iran for President Trump and his team in the White House Situation Room, which was rarely used for in-person meetings with foreign leaders.

Mr. Trump sat down, but not in his usual position at the head of the room's mahogany conference table. Instead, the president took a seat on one side, facing the large screens mounted along the wall. Mr. Netanyahu sat on the other side, directly opposite the president.