Where else to begin, but with Sargeant Joe Rock? The Rock of Easy Company fought his way through World War II--and beyond. Brave and the Bold #108 had him teaming up with Batman to take on the Devil.
Captain Simon Savage may not be as well known as Sgt. Rock or Sgt. Fury, but he also led an eccentric commando squad known as the "Leatherneck Raiders." Those soldiers knew how to surf--which puts them one up on the Howlin' Mad Commandos.
Captain Ulysses "Gravedigger" Hazard outdoes them all. He overcame polio and racism to become a one-man special forces unit and even led Easy Company briefly--but only after he broke into the Pentagon just to prove himself!
Happy Veterans Day to all the nonfictional veterans, too.