It turns out Green Lantern doesn't have to worry about his villains discovering his secret identity because, in a moment of recklessness, Hal Jordan gave away his double life as a superhero himself all because of his impulsivity.
When Hal Jordan was recruited to join the Green Lantern Corps, he took on a new role in addition to his career as a test pilot. He was now a member of the premier peacekeeping organization in the DC Universe and that had to take priority over his life on Earth. Things weren't always easy in his secret identity as Green Lantern, as Jordan was always getting called away from his personal business to attend to matters of universal importance. But Hal managed to strike a balance between keeping his assigned space sector safe and making sure that his private life stayed private.
Related: Hal Jordan's Green Lantern Is Officially a B-List Hero, According to DC
That is until Hal's worst trait inadvertently busted his secret identity wide open. In Green Lantern #2 by Geoff Johns and Carlos Pacheco, Hal runs into his old commanding officer from his Air Force days, General Stone. Back when Hal was a young hotshot, he punched Stone after being chewed out for his reckless behavior. As the Green Lantern continues looking into some strange occurrences around a military base, he discovers that a pair of rogue Manhunter androids are causing the commotion. After a Manhunter drains his Power Ring, Hal tries to get a plane so he can chase after the automatons. Stone, of course, opposes Green Lantern's request, causing Hal to deck the general once more. Hal successfully dispatches the Manhunters but is called to Stone's office later. Stone reveals that he knows Hal is Green Lantern, saying he's only been punched
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