Junaid Hussain originally wanted to be a rapper. As it turned out, the Pakistani kid in Birmingham, England, lived life instead on the internet, and at internet speed. In just a decade, from age 11 to 21, he went from gaming to hacking to killing, an arc the world had never seen before, unfolding faster than anyone might have imagined. For the first half of his digital life, the hacker operated with impunity, bragging in an interview that he was many steps ahead of the authorities: “One hundred percent certain they have nothing on me. I don’t exist to them, I’ve never used my real details online, I’ve never purchased anything. My real identity doesn’t exist online—and no, I don’t fear getting caught.”
By 2015, at age 21, he knew different—he was a marked man, hunted by the United States, the No. 3 leader of the Islamic State in Iraq and Syria (ISIS) on the government’s most wanted list. Living on the run in ISIS-controlled eastern Syria, Hussain tried to keep his stepson close by, ensuring that U.S. airstrikes wouldn’t target him. Inside the Justice Department where I worked at the time, as assistant attorney general for national security, Hussain’s efforts made him a top threat. Nearly every week of 2015 brought a new Hussain-inspired plot against the United States; FBI surveillance teams were exhausted, chasing dozens of would-be terrorists at once.