I can understand that. I am an American History buff, so the 20's through the 70's especially intrigue me. America went through some monumental changes during those years, some for good, some for bad.
But the 50's was a very paranoid time, the Red Scare, Aliens, Atomic War... it was all over the place. This film captured the time period perfectly IMO.
My only knowledge of dealings with Russia and KGB and all that comes from the Greatest American Hero show, as 90% of the time the storylines had to do with the KGB, and I know nothing about the reality of Area 51/ Roswell and all of that, just the fiction of the X-Files and such.
One cool thing in this movie was seeing the Ark exposed during the fight in the beginning.
It's too bad Harrison's so old, I actually would like to see a fith Indy be about his adventures in 1947 that they referred to, but at Ford's age now, a semi-prequel like TOD wouldn't work probably.