Retired Marine Gen. John Allen pinpointed the exact moment he believes the United States began its slide “into illiberalism.”

In a column for Foreign Policy this week, the retired four-star general argued the descent “may well have begun on June 1,” when President Donald Trump threatened to send in troops against anti-racism demonstrators that have spread following the police killing of George Floyd in Minneapolis.

“Remember the date,” wrote Allen, the president of the Brookings Institution who served as commander of the NATO International Security Assistance Force in Afghanistan. “It may well signal the beginning of the end of the American experiment,” he warned.

Allen recalled how Trump railed during a White House Rose Garden press briefing on Monday “against weak governors and mayors who were not doing enough, in his mind, to control the unrest and the rioters in their cities, and threatened to deploy the U.S. military against American citizens.”

“It was a stunning moment,” said Allen. Trump “expressed only the barest of condolences at the murder of George Floyd,” he noted, and “said nothing about the fundamental and underlying reasons for the unrest: systemic racism and inequality.” Allen added that Trump “views those engaged in the unrest and criminal acts in these riots as terrorists, an enemy.”

Allen ended the column on an optimistic note, suggesting that June 1 could also be seen “as a day of hope” and “the beginning of the change of American democracy not to illiberalism, but to enlightenment.”

“But it will have to come from the bottom up. For at the White House, there is no one home,” he concluded, with more one withering swipe at Trump.

Read Allen’s full column here and watch his interview with CNN’s Anderson Cooper on Thursday below: