Sopko said that the Department of Defense, at the request of the Afghan government, restricted information to the public dating back to 2015 that detailed the performance of the Afghan security forces.
"In my opinion, the full picture of what happened in August – and all the warning signs that could have predicted that outcome – will only be revealed if the information that the Departments of State and Defense have already restricted from public release will be made available," Sopko noted at the Military Reporters and Editors Association annual conference.
The withheld information would have helped Congress and the public assess whether the Afghan security forces were a real fighting force or a house of cards waiting to fall, Sopko said, adding that recent events revealed why the Defense Department and Afghan government kept the information secret.
The information would have also helped Congress and the public assess whether the US should have ended its mission in Afghanistan earlier, Sopko noted.
The Taliban took control of Afghanistan in mid-August and set up a new government, led by Mohammad Hasan Akhund, who served as the foreign minister during the previous Taliban rule and has been under UN sanctions since 2001.
*A terrorist organisation outlawed in Russia and many other countries