From CNN

A member of the Defense Business Board has resigned in protest at the Trump White House's recent purge of the board's membership, replacing members with arch Trump loyalists and campaign staffers.

"The abrupt termination of more than half of the Defense Business Board and their replacement with political partisans has now put the nation's safety and security at risk," Steve Blank wrote in his letter of resignation to acting Secretary of Defense Christopher Miller.

Blank, a longtime entrepreneur, wrote: "My service to the Department of Defense was a service to the country, not to a party. I hereby tender my resignation."

Last week, the Pentagon confirmed that nine members of the Defense Business Board had been purged, replaced with Trump partisans including Corey Lewandowski and David Bossie.

Blank is recognized for developing the customer development method that launched the lean startup movement, a methodology which recognized that startups are not smaller versions of large companies, but require their own set of processes and tools to be successful. His Lean Launchpad class (taught as the National Science Foundation Innovation Corps, or I-Corps) has become the standard for commercialization for all federal research.

Blank writes and teaches about customer development and the lean startup method. He is an adjunct professor of entrepreneurship at Stanford lectures at the UC Berkeley Haas School of Business, and is a senior fellow at Columbia University. He has written four books: The Four Steps to the Epiphany, Not All Those Who Wander Are Lost, The Startup Owner's Manual, and Holding a Cat by the Tail.