Before they ever had beef in the Corps, two of Earth's most famous Green Lanterns were already at one another's throats. A glimpse at Hal Jordan's secret origin showed how he and John Stewart got off on a bad foot years before the two served on the same team.
Hal Jordan was the first person from Earth to be picked to join the cosmic peacekeeping organization, the Green Lantern Corps, but he wouldn't be the last. Though Sector 2814 already had a reserve Lantern in Guy Gardner, the Guardians were forced to replace him after Guy was injured saving a civilian. John Stewart became a Green Lantern, though Jordan was not exactly pleased about it, believing Stewart wasn't a good fit. The two didn't initially see eye-to-eye on a number of issues, but over time Hal and Jordan did come to respect one another as Lanterns and even became friends.
Related: Hal Jordan's Green Lantern Is Officially a B-List Hero, According to DC
But still, it's odd that Jordan was so against John's initial recruitment into the Corps. However, a brief incident from both their pasts may shine a light on how the two developed an animosity. In Green Lantern #29 by Geoff Johns and Ivan Reis, Hal Jordan's time before he became a part of the Green Lantern Corps is explored. After running away from home on his 18th birthday, he finds the place where he belongs when he signs up with the Air Force. One night during some downtime in a local watering hole, Jordan notices a Marine being rough with a woman. When the Marine presses on with his manhandling, Hal decks him, catching the attention of the Marine's comrades, including Jordan's future partner, John Stewart. Things get out of hand and lead to a giant brawl in the bar, with Jordan and Stewart slugging it out
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