As much as Sinestro despises the Green Lanterns, he actually helped them become a much more valuable asset to the Justice League. The villain used his brashness to help overturn a policy that would, ironically, make his future rivals a much more resilient force.

Fans of the Green Lantern mythos may recall that, at one time, Sinestro was a member of the Corps and was one of its most dedicated officers. No one took the oath of the Lanterns more seriously than Sinestro, even though he didn't always agree with the Guardians of the Universe's direction of the Corps. After Hal Jordan became a Green Lantern, Sinestro saw that for all of Jordan's uncouth, Earthman behavior, he had a new ally in the Corps. Jordan often agreed with Sinestro in how the Guardians were usually the biggest obstacles when it came making real and effective change in the Corps.

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As it turns out, the seasoned and rookie officers were instrumental in making a change in the Corps that drastically effected the future of the Green Lanterns. In Green Lantern #35 by Geoff Johns and Ivan Reis, Jordan and Sinestro are summoned to Oa over a violation of protocol for their extended fraternization. Sinestro and Hal Jordan have violated the number one rule in the Corps which is intermingling outside of their assigned sectors. Sinestro takes lead on their defense, saying that their mission required extended time together, only to receive a reprimand from the Guardians. Hal, on the other hand, pushes back saying the fraternization edict is based on the Guardians' fear of the Lanterns working together and overthrowing their leaders. Though Hal is threatened with expulsion, Sinestro agrees with his mentee, arguing that the Corps is stronger by working together instead of separately.

Hal Jordan Sinestro Green Lantern Rules DC Comics

Before Hal Jordan and Sinestro helped change their organization, Green Lantern Corps officers were limited to one per sector (on top of the no-fraternization edict). But by making the case that the Lanterns were more effective together, Sinestro helped pave the way for additional Lanterns in each sector. And, considering how many Lanterns have come from Earth, Sinestro helped give the Justice League a veritable trove of Lanterns to join their ranks.

More often than not, the League has had a Lantern in their ranks to give them some serious firepower. But not every Lantern possesses the same benefits. John Stewart is a better tactician, while Kyle Rayner’s positives as a Green Lantern are undoubtedly his creative constructs. Having greater numbers doesn't just bring about strength for the Lanterns, it brings variety, something extremely beneficial for a team as powerful as the Justice League. By helping reform the Guardians' most strict policy, Sinestro allowed Earth a chance for a diverse coalition of Lanterns to thrive. This may have not served him well as an enemy of the Green Lanterns, but it did wonders for the Justice League.

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