[wintertime]

How are you going to keep them down on the farm after they've seen...the farm?
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Could you expand on this? To whom is the “them” referring?

And..The “farm” is a metaphor for what?

[Coyoteman]

How are you going to keep them down on the farm after they've seen...the farm?

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Could you expand on this? To whom is the “them” referring?

And..The “farm” is a metaphor for what?

The line comes from a song written after WWI. The song, How You Gonna Keep 'Em Down On The Farm After They've Seen Paree? (1919), was written by Lewis and Young and the music was by Walter Donaldson (1893-1947).

It refers to the problem of keeping soldiers returning from the war in Europe working on the family farms after they saw the wide world (i.e., Paris).

I hope this helps you understand my post.