The seal at the U.S. embassy is clearly fake. The eagle is holding a trident instead of a bundle of arrows.
The establishing shots of Washington, D.C. are clearly from the 21st century and not the 1970s, as the World War II Memorial (built in the 2000s) is visible.
When Secretary Kim arrives at Dulles International Airport, you can see a large parking garage in the background. The scene is set in the 1970s and that garage wasn't built until 2002.