36 years ago - Thomas Andrew Tresser is born.
18 years ago - 18-year-old Thomas goes to college.
14 years ago - 22-year-old Thomas graduates, and is recruited by the CIA.
11 years ago - 25-year-old Thomas's brother is killed. He discovers that he was killed by his own agency, and goes rogue to bring down S.H.A.D.E.
7 years ago - 29-year-old Thomas brings down S.H.A.D.E. with the help of Caitlin Fairchild, and turns himself in to Checkmate.
6 years ago - 30-year-old Thomas is given clemency by Director Bones in exchange for his service as the new agency liaison for the Freedom Fighters.
5 years ago - 30-year-old Thomas becomes a DEO agent when Director Bones moves the Freedom Fighters under their control.
Even though a lot of us first met Thomas Tresser when Allen Heinberg introduced him in the pages of Wonder Woman as her new partner, he actually had a pretty illustrious career of his own.
A rogue agent taking down a unnamed government agency, Tresser was featured in several back-up stories in Brave and the Bold. They were cool stories, cementing him as the DC equivalent of Marvel super-spy Nick Fury. He was later a mainstay of the Suicide Squad where his mastery of disguise was actually used to retcon several story elements.
Still, there's a very clear distinction to be made between the classic character's appearances and his modern ones, where he was used as a romantic foil for Wonder Woman. There's certainly precedent for this sort of relationship in Wonder Woman's stories. The Diana/Tresser relationship is obviously a new version of the classic Wonder Woman/Steve Trevor dynamic.
From the very beginning, Steve Trevor was a part of Wonder Woman's world, serving as her partner, romantic interest, and even husband in later stories. While on the surface, it seems pretty unpleasant that Wonder Woman needed a male character to give her 'legitimacy' in the eyes of the reader, the fact is that It was almost always Diana that was saving Steve. Even better, Steve was never diminished as a character or as a man for accepting Wonder Woman as an equal, or for differing to her as a more powerful person. He accepted her strength, and that gave readers permission to do the same.
It might be argued that it's a little problematic that readers in 2005 would need the same hand-holding approach to accepting a female superhero as 'legitimate' that readers needed in 1940. Nonetheless, Wonder Woman exists in a world where the way people perceive gender matters, and there's an undeniable wisdom in just depicting them as they happen.
However, it has to be said... Tommy is no Steve Trevor. The relationship between Steve and Wonder Woman (Hippolyta in our timeline) is pretty classicaly heteronormative, and the modern Wonder Woman is so much more interesting than that.
We've used him for even more, making him our modern liaison with our Freedom Fighters team. There's obviously precedent for this in his time with the Suicide Squad, but it also brings him into the DEO, the place where he winds up working with Wonder Woman.
Also, we've expanded his initial story a bit, by actually naming the rogue organization he goes after. We've slowly used S.H.A.D.E. for more and more stories, every time we needed a shady, nefarious organization that does things it probably shouldn't. It's a slightly different take on an organization that, in the comics, is at least semi-altruistic. Still, it just keeps fitting our larger purposes. This means that, for Tresser's story to work, he actually has to succeed at taking S.H.A.D.E. down. it would be a GREAT story, but we had to pick through the rest of our timeline and make sure we hadn't stripped anyone else of a story element too early. We've had to make a few adjustments to make sure that S.H.A.D.E. has no further effect on the timeline after Nemesis's defeat of the organization seven years ago, but now we're in good shape, and we have a cool character out of it.