False.
He was special forces and his service record is fully classified at the highest level. He's been disavowed by the military because to acknowledge he existed would threaten national security.
If some of his missions were revealed, allies would become enemies. Treaties would be invalidated. National borders would have to be redrawn. We'd risk a major international conflict on three sides if it went public.
Mr. Rogers was one of the fiercest soldiers that ever lived. He could topple governments solo. He was one of the finest snipers in US military history... He was known to the communists only as 'breath of the night wind' and he was feared everywhere behind the Iron Curtain. It was said he could get a killshot at a range of a mile and a half, and cleanly escape his sniper's nest before the sound of the bullet made it to the corpse of the dictator he shot.
He could hold his breath for over nine minutes during an amphibious assault while dragging a tow line in his teeth. He was lethal with any blade more than three quarters of an inch at a range of fourteen feet in hand-to-hand combat. He once liberated an entire village singlehandedly, against a warlord with 50 guerrilla soldiers. He once snuck behind enemy lines with only the cigar between his teeth, and torched an Afghani poppy field of such massive acreage that the entire opium economy collapsed for three years.
Three of the characters in "Inglorious Basterds" were based on him, because they thought it was too unrealistic to say that just one man could do it all. That's the bloodthirsty killing machine everyone else sees as the kind old man in the cardigan sweater. When he turned his back on war and became a pacifist, some say it was because he was haunted by all he had done. Others say it was because he'd just run out of people to kill.