Today, the White House confirmed that cybersecurity coordinator Rob Joyce will head back to the National Security Agency, where he previously ran the nation’s top hacking team. His departure comes just a week after Tom Bossert[1], Trump’s cybersecurity czar and Joyce’s boss, was forced out—and leaves the administration without two trusted voices on one of the most important challenges the US faces going forward.

While Bossert’s exit appears to have been engineered by recently installed national security advisor John Bolton, Reuters reports[2] that Joyce will leave of his own accord. But whatever the reasons for their respective absences, losing them will slow the ability of the US to think about big-picture cybersecurity concerns. And replacing them may not be easy.

'Even though no one should be surprised, it doesn’t mean it shouldn’t be an outrage.

Jason Healey, Columbia University

To understand the impact of losing both Bossert and Joyce, it’s important to understand exactly what it is they do. As homeland security adviser, Bossert’s purview extended beyond cybersecurity specifically, but America's security from digital threats has nonetheless been an area of particular focus for him since he served as deputy homeland security advisor in George W. Bush’s second term. It was Bossert who called out[3] North Korea for the WannaCry ransomware that threatened to seize up computers around the world in a recent Wall Street Journal editorial, and who briefed[4] the nation on Trump’s cybersecurity executive order[5] last fall. He was also seen as a potentially stabilizing force[6] in a freewheeling administration.

Joyce, meanwhile, brought serious hacker bona fides[7] to the White House earned after years of running the NSA's elite hacking team known as Tailored Access Operations.

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