It could be that a tense disagreement over the now-dead deal with the Taliban was the last straw for Trump, who said he fired his National Security Advisor John Bolton today. The firing followed a “bitter argument last night” Bolton said he had with Trump over the president’s plan to host Taliban leaders at Camp David three days before the 9/11 anniversary, sources report.

“I informed John Bolton last night that his services are no longer needed at the White House. I disagreed strongly with many of his suggestions, as did others in the Administration, and therefore I asked John for his resignation, which was given to me this morning,” Trump tweeted late this morning. “I thank John very much for his service. I will be naming a new National Security Advisor next week.”

While Trump has dumped high profile members of his administration via tweet repeatedly in the past, this may be the first time that an official hit back at the president’s narrative so immediately and directly—a signature of Bolton’s overall modus operandi, and likely what put him so much at odds with the administration.

Just minutes after Trump’s tweet, Bolton quickly went into action, leveraging his four decades of contacts inside the Beltway to advance a completely different narrative by texting seemingly every reporter in his contact list.

“John Bolton just texted me, just now, he’s watching,” said Brian Kilmeade of Fox News while live on television. “He said, ‘let’s be clear, I resigned.'”

“Offered last night without his asking,” Bolton texted to Peter Baker of the New York Times. “Slept on it and gave it to him this morning.”

Bolton followed his flurry of text messages with a public tweet twelve minutes after the president’s: “I offered to resign last night and President Trump said, ‘Let’s talk about it tomorrow.'”

But Bolton’s version of events doesn’t make much sense: about an hour before Trump’s tweet, the White House had informed the press that Bolton would be briefing reporters, along with Secretary of State Mike Pompeo and Treasury Secretary Steve Mnuchin, and  Bolton even led a meeting this morning.

In yet another example of the discord that Bolton fostered within Trump’s cabinet, reporters noted “palpable tension” in the West Wing as Bolton’s team competed with White House aides to advance opposing narratives to reporters waiting in the wings.

“A pro-Bolton NSC official came to speak with reporters inside the West Wing when Press Sec[retary] Stephanie Grisham walked by, gave a look and said: ‘Oh look, right outside my office’ as she walked past,” tweeted NBC News’ Peter Alexander.

Bolton has been at odds with President Trump for months, and his imminent departure has been frequently predicted.

In a show of power late July, a Bolton representative forced White House chief of staff Mick Mulvaney to deny that Trump was weighing options for Bolton’s replacement and that Mulvaney himself favored Bolton’s departure.

Yet the writing was on the wall for Bolton for some time, in part because he had a habit of leaking information to the press that would damage negotiations he didn’t agree with. The situation became so bad that Trump’s special envoy Zalmay Khalilzad reportedly refused to allow Bolton to leave the room with a copy of the nascent Afghanistan deal. That decision was followed by a flurry of pro-Bolton leaks and and anti-deal coverage in the press.

Trump and Bolton long battled over several critical foreign policy issues including North Korea, Iran, and Venezuela. Trump liked to joke that Bolton is always hoping to enjoy a war somewhere, and many speculated that he might be Trump’s foil in negotiation proceedings.

But in recent days, it appears Trump became frustrated with Bolton publicly contradicting him and scuttling his negotiations. Bolton opposed Trump’s face-to-face negotiations with North Korean leader Kim Jong Un, backed an unsuccessful campaign to remove Venezuela’s President Nicolás Maduro from power, and promoted an aggressive stance towards Iran. The argument over the Camp David Taliban deal might have made their final break inevitable.

Secretary of State Mike Pompeo, who often clashed with Bolton, was asked at a Tuesday afternoon press conference if he was “blindsided” by Bolton’s firing. Pompeo responded, “I’m never surprised.”

Bolton was Trump’s third national security advisor, following Michael Flynn and H.R. McMaster. Given that Bolton is an unapologetic Bush-era war hawk who has advocated for regime change in Iraq, Syria, Libya, Yemen, Cuba, Venezuela, North Korea, and Iran, his tenure was guaranteed to be rocky. Trump campaigned against costly foreign interventionism, while Bolton was a key architect of the 2003 war in Iraq.

In response to a question about how Bolton’s foreign policy philosophy was out of alignment with the president’s, Mnuchin volunteered, “The president’s view of the Iraq war and ambassador Bolton’s was very different, the president’s made that very clear.”

A note of caution for doves that hope Bolton’s exit signals that Trump’s foreign policy will align with his campaign promises: both Mnuchin and Pompeo avowed during their very brief press conference that the “maximum pressure” campaign against Iran and sanctions against both the Islamic Republic and other terrorist organizations would continue apace. With Bolton gone, Pompeo and his hawkish views will have the unobstructed ear of the president.

Barbara Boland is The American Conservative’s foreign policy and national security reporter. Follow her on Twitter @BBatDC.