O'Brien is currently the special presidential envoy for hostage affairs. Waddell served as Trump's deputy national security adviser. Fleitz is a Bolton ally who served as executive secretary of the NSC last year. Gordon-Hagerty is the Energy Department's undersecretary for nuclear security. And Kellogg is the national security adviser to Vice President Mike Pence.
Trump had said after Bolton departed last Monday that he hoped to name a new national security adviser this week.