The Unknown Soldier is the darkest and most enigmatic of DC's World War Two heroes. He's a master of disguise, but his real face is so disfigured that he wears bandages like the Invisible Man. He specialises in espionage and counterintelligence, but has been known to blow his own cover by losing his temper at enemy atrocities.
The character was created in 1968 by Joe Kubert, Robert Kanigher and Irv Novick, for a Sgt. Rock story. Four years later, he got his own series in Star Spangled War Stories, which eventually changed its title to The Unknown Soldier, and that ran from 1970-1982. He got a twelve-issue limited series by Jim Owsley and Phil Gascoine in 1988-89, which did well in the Comics Buyer's Guide Fan Award for "Favorite Limited Series". After that, Vertigo snaffled him. Garth Ennis wrote this mini-series in 1997, then Joshua Dysart followed in 2008 with a 25-issue series that got cancelled for low sales but was nominated for an Eisner Award for "Best New Series of the Year". (War stories don't sell well these days, despite the best efforts of Garth Ennis.)
This mini-series is dark. It's akin to Garth Ennis's Fury: My War Gone By in that it's addressing America's inglorious record with wars and covert operations after World War Two. The Unknown Soldier saw Dachau, went berserk and started machine-gunning German prisoners. "The world should know! If this is what our enemies do -- if this is what America must fight -- then we are always right! And anything we do is right!"
He kept busy in subsequent decades. He went into Iran, in a scene that reads very differently in the light of Donald Trump's actions today. "Or we will bomb Iran back into desert. And I will come for you." That's in 1953, under the Shah, and the book's fully aware of the consequences of that meddling.
He did covert operations. He tricked his own side into massacring civilians. And, today, if you're a young, idealistic CIA agent who's trying to hunt down the truth, you might find that asking questions triggers a mass termination order on everyone who's ever spoken to the man.
It's a simple story, but very Ennis. (Wikipedia thinks he ignored the 1988-89 limited series, but I haven't read that and I can't provide any details.) The new characters are interesting and have sanity issues. Agent Clyde starts talking to a dead colleague, even though she tells him she doesn't exist any more, this is unhealthy and he should stop. There's someone called Screwball whom the CIA use for wetwork even though she cut her parents' throats when she was eight and had to be recruited from a lunatic asylum. The Unknown Soldier himself has something he wants too. He's an old guy by now, although still in terrifying physical shape. Ennis has since covered similar ground in other books, but it's the Unknown Soldier himself and his goals that makes this particular story stand out from that oeuvre. It's good stuff and I'd happily read the Dysart series too if I stumbled across it.