Sebastian Gorka is resigning his post as Deputy Assistant to President Trump, multiple sources familiar with the situation have told The Federalist.

In a blunt resignation letter, the national security and counterterrorism expert expressed dissatisfaction with the current state of the Trump administration. “[G]iven recent events, it is clear to me that forces that do not support the MAGA promise are – for now – ascendant within the White House,” Gorka wrote. “As a result, the best and most effective way I can support you, Mr. President, is from outside the People’s House.”

Gorka’s letter expressed unhappiness with the direction the Trump administration’s foreign policy has taken, as signaled by the president’s recent speech on Afghanistan:

“Regrettably, outside of yourself, the individuals who most embodied and represented the policies that will ‘Make America Great Again,’ have been internally countered, systematically removed, or undermined in recent months. This was made patently obvious as I read the text of your speech on Afghanistan this week…

“The fact that those who drafted and approved the speech removed any mention of Radical Islam or radical Islamic terrorism proves that a crucial element of your presidential campaign has been lost…

“Just as worrying, when discussing our future actions in the region, the speech listed operational objectives without ever defining the strategic victory conditions we are fighting for. This omission should seriously disturb any national security professional, and any American who is unsatisfied with the last 16 years of disastrous policy decisions which have led to thousands of Americans killed and trillions of taxpayer dollars spent in ways that have not brought security or victory.”

During his time in the Trump administration, Gorka focused on issues such as countering the Muslim Brotherhood, the crisis in Qatar, supporting efforts to draft a new long-term national security strategy, and combatting China’s economic warfare. Before coming to the White House, Gorka was the Major General Matthew C. Horner Chair at Marine Corps University and also contributed to Breitbart News.

Gorka’s tenure at the White House was marked by unusually vociferous attacks against him and his family by left-leaning media organizations and the Democratic Party. This includes personal attacks against his wife, mother, and son.

A source close to the White House said of his decision, “This was more or less going to be a done deal when Bannon submitted his resignation. Not because he didn’t have a protector, but because there is no point in having your life ruined every day if you’re not going to get much accomplished.” The same source said that what did change after Bannon left was that anti-Bannon factions began erecting bureaucratic road blocks to undermine Gorka internally.

The Forward has written dozens of attack pieces against Gorka, including several attempting to align him with Nazism. Most recently that publication retracted a story about his son’s schoolwork. Gorka strenuously objected to allegations he had ties to Nazi groups in his family’s home country of Hungary, where he had previously been involved in national politics. Even detractors eventually acknowledged the Nazi accusations were unfair smears.

In his letter, Gorka made clear that he believes in the promise of the Trump presidency despite being concerned about its present direction.

“Your presidency will prove to be one of the most significant events in modern American politics. November the 8th was the result of decades during which the political and media elites felt that they knew better than the people who elect them into office. They do not, and the MAGA platform allowed their voices to be heard,” he wrote, adding, “Millions of people believe in, and have chosen, you and your vision of Making America Great Again. They will help eventually rebalance this temporary reality.”

UPDATE: In response to this story, an anonymous White House official reportedly said, “Sebastian Gorka did not resign, but I can confirm he no longer works at the White House.”