[Publius]

They did a good job on a very limited budget. Los Angeles stood in for New York, the Union Pacific stood in for Taggart Transcontinental, and Chicago commuter cars and rail yards stood in for passenger trains and Philadelphia.

UP even let them film a "track blitz" where they use a machine to lay track without huge crews of men.

They got a lot of bang for the buck.

[Borax Queen]

Wow, thanks for the background, interesting!

The footage at the very beginning was frightening, especially as I heard what sounded like the Communist’s voice in the White House. And every city background scene looked like too much of the country does already (the bums, etc.).