Edward Price joined up in 2006 and was "convinced that it was the ideal place to serve my country". He became a terrorism expert and worked under the George W Bush and Barack Obama administrations, recently serving on the staff of the National Security Council, and believed he would never leave.
But he said the President's actions, including his poorly-received speech at the agency's Langley headquarters and—the "final straw"—his decision to elevate Steve Bannon to the principals committee of the National Security Council, and the removal of the director of national intelligence.
The National Security Council’s principals committee is the top interagency group for discussing national security. In a re-drafting of his plans Mr Trump later named CIA director Mike Pompeo to the committee.
Writing in the Washington Post, he said: "The administrations of George W Bush and Barack Obama took the CIA’s input seriously. There was no greater reward than having my analysis presented to the president and seeing it shape events. Intelligence informing policy—his is how the system is supposed to work.
"Trump’s actions in office have been even more disturbing. His visit to CIA headquarters on his first full day in office, an overture designed to repair relations, was undone by his ego and bluster ... bragging about his inauguration crowd the previous day.
"Whether delusional or deceitful, these were not the remarks many of my former colleagues and I wanted to hear from our new commander in chief."
Mr Trump later said in a Fox News interview: "I gave the speech that really was a 10, relatively speaking. I had a standing ovation like you wouldn’t believe. Everybody. And it was such a success.
"I paid great homage to the wall with the stars. I paid great homage. The audience was standing ovation. They were standing from the beginning. They didn’t even sit down."
Axing the director of national intelligence as a principal showed the White House was "tuning out the intelligence professionals", Mr Price said.
He added: "the White House’s inclination was clear. It has little need for intelligence professionals who, in speaking truth to power, might challenge the so-called 'America First' orthodoxy that sees Russia as an ally and Australia as a punching bag.
"That’s why the president’s trusted White House advisers, not career professionals, reportedly have final say over what intelligence reaches his desk."
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