WASHINGTON -- He is known as the Dark Prince or Ayatollah Mike, nicknames he earned as the Central Intelligence Agency officer who oversaw the hunt for Osama bin Laden and the American drone strike campaign that killed thousands of Islamist militants and hundreds of civilians.

Now the official, ------- -------, has a new job. He is running the C.I.A.’s Iran operations, according to current and former intelligence officials, an appointment that is the first major sign that the Trump administration is invoking the hard line the president took against Iran during his campaign.