[quote=@Dead Cruiser]

Maybe we need a fictional history for each org.

My idea is like... Avengers were formed as an unofficial alliance of Allied superheroes in WWII. Later grandfathered into SHIELD following the formation of the United Nations.

The Justice League was originally the Justice Society of America, and was also formed after WWII by the likes of Alan Scott, Jay Garrick, Carter Hall, etc. Membership changes and bankrolling from Wayne changed it from basically a drinking club for veteran superheroes into the global defense alliance it is today as the Justice League.
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