Ron Conway, a prominent Silicon Valley venture capitalist who was an early investor in Google, Facebook, and several other notable tech giants, resigned Thursday from the board of the Salesforce Foundation after the company’s chief executive, Marc Benioff, said last week that he fully supported President Trump and wanted the National Guard to come to San Francisco. The Salesforce Foundation, which had roughly $400 million in assets by the end of 2023, aims to help disadvantaged students, mainly by trying to improve tech literacy and college preparation.

Conway, who had been a member of the Salesforce Foundation board for a decade and has been a close friend of Benioff’s for more than 25 years, told Benioff in a fiery email that their values were no longer aligned and that he was resigning as a director. The email, seen by the New York Times, laid bare the rift between two of San Francisco’s best-known tech figures over Benioff’s political shift and his controversial call for federal troops to be deployed in the city.

“It saddens me immensely to say that with your recent comments, and failure to understand their impact, I now barely recognize the person I have so long admired,” Conway, a top Democratic donor, wrote to Benioff in the email.

Conway was so disturbed by Benioff’s comments that he contacted his longtime friend about them, and they discussed the matter over the past few days, according to the email. But Conway did not come away satisfied that Benioff had reflected on the dangers posed by the Trump administration or the impact of his remarks.

“I have expressed candidly to you, repeatedly, in recent days, that I am shocked and disappointed by your comments calling for an unwanted invasion of San Francisco by federal troops,” Conway wrote in the email, “and by your willful ignorance and detachment from the impacts of the ICE immigration raids of families with NO criminal record.”

San Francisco backlash

The resignation came after Benioff told the New York Times in an interview last week that he backed President Trump and thought National Guard troops should be deployed in San Francisco, where Salesforce is based, to help prevent crime. The comments by Benioff, a billionaire who had been considered Silicon Valley’s rare progressive tech titan, enraged leaders in the liberal city.

Conway told Benioff that San Francisco—“where you don’t even live or vote”—was trying hard to reduce crime and boost its police ranks. Since the pandemic began, Benioff has lived on the Big Island of Hawaii, where he has bought several parcels of land. He is registered to vote there, not in San Francisco.

President Trump said on Wednesday that San Francisco could be the next place he sends National Guard troops, and that he appreciated the “great support” for such a deployment, a possible reference to Benioff and to Elon Musk, who also backed the idea. Though Trump has touted his use of the military to fight crime, troops are generally forbidden by law from engaging in domestic law enforcement.

Leaders in San Francisco have condemned Benioff for his remarks and for suggesting the president should send troops to the city. Mayor Daniel Lurie released new statistics this week that showed homicides in San Francisco were at a 70-year low and that drug overdose deaths have also dropped.

Benioff is busy running Dreamforce this week—but while he’s previously said San Francisco is “a lot more fun than Vegas,” he’s also threatened in the past to move the event to Las Vegas, citing safety reasons, according to the Times.

“Your obsession with and constant annual threats to move Dreamforce to Las Vegas is ironic, since it is a fact that Las Vegas has a higher rate of violent crime than San Francisco,” Conway wrote. “San Francisco does not need a federal invasion because you don’t like paying for extra security for Dreamforce.”

Benioff has mostly avoided discussing Trump, ICE, H-1B visas, and immigration during Dreamforce this week—Fortune’s Jeremy Kahn was on the scene, and asked Benioff about this directly—but he said Tuesday that he just cares about everyone’s safety. Benioff did not immediately respond to Fortune’s request for comment about Conway’s resignation. But in a statement to Fortune, a Salesforce spokesperson offered a measured response to Conway’s resignation, saying, “We have deep gratitude for Ron Conway and his incredible contributions to the Salesforce Foundation board for over a decade,” noting the company’s all-time giving of $840 million to educational causes and public schools.

Ron Conway skewers Marc Benioff in board resignation after 25 years: ‘I now barely recognize the person I have so long admired’