A new report from the U.S.’ Special Inspector General for Afghanistan Reconstruction, or SIGAR for short, says former President Donald Trump and President Biden’s decisions to withdraw U.S. forces and contractor support from Afghanistan were the “single most important factor” in the Afghan military’s swift collapse in August of 2021,  Politico reports.

The SIGAR document, released Wednesday, is the first government report discussing how and why Afghan forces crumbled.

“We built that army to run on contractor support. Without it, it can’t function. Game over,” a former U.S. commander told the watchdog’s office, per the report. “When the contractors pulled out, it was like we pulled all the sticks out of the Jenga pile and expected it to stay up.”

“There was a red light blinking on Afghanistan for years saying ‘watch out,'” watchdog John Sopko told Politico. “Once the morale collapsed, that was it.”

While the document does serve to confirm certain previous reporting, it also sheds “new light on the intrigue and suspicion that consumed the Afghan leadership in its final days,” writes The Washington Post.

For example, the report reveals how former Afghan President Ashraf Ghani was paranoid Afghan forces would turn against him, and thought the U.S. was working behind the scenes to remove him from power, per the Post. It also concludes that Trump’s agreement with the Taliban and the subsequent decision to withdraw U.S. forces by May 2021 had a tragic effect on the Afghan’s military morale, Politico notes.