Kindle. Some days all you want to read is an airport novel and can't remember why you picked this one. (Scavenging the various memory holes shows that David S suggested Harris's The Ghost, but the movie version of that put me off.) I have some vague memories of learning something from the Frederick Forsyth books I read back when I was a kid, which is unfortunately not the case here.
Briefly: Circa 1992 Harris served up this alternate history of circa 1942 to 1964 in which the Nazis, having won World War II, establish a co-prosperity sphere bearing a strong resemblance to the actual EU. This rich conceit is squandered with the central McGuffin (spoiler) being that the Holocaust still happened but was successfully turned into #fakenews. I had hoped for tales of something supernatural dug from the cold dead ground under the streets of dreary Zurich instead of this replaying of old PK Dick moves. Perhaps Harris was reflecting on the denialism of the day, which has since gone toxically viral.
There is much Speer architecture. There are loads of SS officers. The lead is investigating a murder, later murders, and of course gets into bed with a freedom-loving American journalist/girl. Even-handedness is attempted by yammering on about Joseph P. Kennedy's antisemitism. The smoking is similarly endless. The "German look" and sundry totalitarian imaginings are drawn straight from 1984. The writing is workman-like, not too patronising, and does what it needs to do.
Rutger Hauer starred in the 1994 movie. Apparently the adaptation was loose.
Loads of opinions at Goodreads. It seems Harris has form for cloning earlier plotlines: the summary of Archangel reads just like The Boys from Brazil with Stalin subbed for Hitler.