Fans of Green Lantern, Arrow, and David Ramsey have long speculated that John Diggle may actually be John Stewart.
The fan theory is that when Diggle was in the military, he changed his name (for whatever reason).
Now it's learned that the theory might not be too far off as David Ramsey has confirmed there are talks that Diggle might become Green Lantern.
Ramsey confirms the Green Lantern possibility in a recent interview (via Screen Rant):