It's kind of incredible to look back at this whole stretch of comics, dating all the way back to the '60s, and realize that, before James Gunn got his hands on him... Peacemaker was just no good as a character.
Created by Joe Gill at Charlton Comics as a politically-themed superhero-- "a man who loves peace so much he's willing to fight for it"-- the character was clearly meant as a conservative fantasy about being the mature, morally-responsible adult in the room AND being the brash man-of-action who gets the job done at the same time. "You can't blame ME for blowing up that submarine! These dangerous lunatics gave me no other choice! All of my diplomatic options had failed!" It's pretty transparent, and the comics are mostly kinda dull.
When the character was revived by DC-- shortly after Alan Moore had used the Charlton characters as the template for the anti-heroes of Watchmen-- Peacemaker was re-imagined by Paul Kupperberg as an outright maniac: a delusional and dangerous man who believed himself an upstanding, righteous hero. The BEST use of this version of the character is as an antagonist in Kupperberg's Vigilante run; a relentless, delusional murderer kinda makes SENSE as a bad guy, right?
Alas, this was the late '80s, and grim, obsessive killers like Wolverine and the Punisher were all the rage. So DC made a go of turning Peacemaker into a protagonist-- giving him a four-issue solo miniseries by Kupperberg, and then working him into the Checkmate comics as a recurring guest star. And the results are... pretty dire. Peacemaker is a one-note character whose only defining trait (outside of being a TOTAL BADASS) is that he near-constantly hallucinates that his dead Nazi father is in the room with him, berating him and encouraging him to be more violent. Which means that so, SO much of this book is taken up by scenes of a literal Nazi just being a monstrous sh*thead and saying deeply unpleasant things.
It's not great.
Worse, the back half of this collection is taken up by excerpts from Checkmate and Eclipso issues... but only the pages pertaining to Peacemaker, so there are all these random characters and plotlines whirling around him that never get adequately explained or resolved. (There's also a five-part story from Showcase '96 by Mike Baron that may legitimately be one of the worst comics I've ever read.)
I love these DC Finest collections, and a definitely appreciate the focus on individual characters and their broader histories, but... WOOF. This guy really needed to become a joke to work!