Johnson, the subject of Don't Die: The Man Who Wants to Live Forever, has taken enthusiasm for life- and health-hacking to its most well-known extreme.
Ahead of April 5, Trump has stated he would like "to see TikTok remain alive" in the U.S., as there are "a lot of potential buyers" interested in the platform.
Former members of the defense and intelligence communities wonder who's in charge of policy and operations -- and if they're qualified for the responsibilities.