Battered and bloodied after just barely saving the world from an alien invasion, anti-hero Peacemaker (John Cena) and his surviving teammates are headed away from the battlefield to get medical treatment when the Justice League finally arrive, too late to help.

So, there still was a Justice League of America. Only some characters, specifically Wonder Woman, were no longer part of its early history. So when post- Crisis comics retold the formation and early years of the Justice League?

Peacemaker season 2 episode 1 retcons a big moment from last season's finale – and it needed to for storytelling reasons.