In his last letter to his parents, U.S. Army Sergeant Bowe Bergdahl, who is now at the center of a controversial prisoner-swap agreement between the U.S. and the Taliban, had called the U.S. army the “biggest joke” and that it needed to be laughed at, according to a 2012 report in Rolling Stone magazine.

Bergdahl, who was released by the Taliban on Saturday in exchange for the release of five high-ranking Taliban members from the Guantanamo Bay prison, wrote in a letter that the commander of his platoon was a “fool” while acknowledging that the Afghans needed help. The letters, which were published by Rolling Stones magazine in 2012, address Bergdahl's time in the army and his subsequent capture by the Taliban in 2009, and portray a soldier who seems sensitive to the issues faced by Afghans while being disillusioned with the army's role in the troubled country.

“The US army is the biggest joke the world has to laugh at,” Bergdahl wrote in an e-mail to his parents, according to Rolling Stone magazine, adding: “It is the army of liars, backstabbers, fools, and bullies. The few good SGTs [sergeants] are getting out as soon as they can, and they are telling us privates to do the same.”

Bergdahl joined the army when it was short of soldiers to be sent to Afghanistan, and was deployed after 16 weeks of rigorous training. Once in Afghanistan, he sent back frequent dispatches of his experiences, which included descriptions of attacks by the Taliban on the local population, according to the magazine report, and he was also reportedly deeply disturbed by an incident where an American vehicle ran over a local child. And, according to fellow platoon members, cited by the magazine, he spent more time with the Afghans than with his own team. 

When Bergdahl was moved to another unit, he wrote: “One of the biggest s**t bags is being put in charge of the team” referring to the new team’s leader as a “conceited old fool.” 

Bergdahl also wrote: “In the US army you are cut down for being honest... but if you are a conceited brown-nosing s**t bag you will be allowed to do whatever you want, and you will be handed your higher rank.”

Bergdahl has been called a deserter by many in the army who have openly opposed U.S. President Barack Obama’s decision to arrange his freedom in exchange for the Taliban prisoners.

“I am sorry for everything here. These people need help, yet what they get is the most conceited country in the world telling them that they are nothing and that they are stupid, that they have no idea how to live,” Bergdahl said in his mail, according to the Rolling Stones.