He wrote it partially in protest to Irving Berlin's "God Bless America". The original version contained the verses at the end:

There was a big high wall there that tried to stop me;
Sign was painted, it said private property;
But on the back side it didn't say nothing;
This land was made for you and me.

In the squares of the city, In the shadow of a steeple;
By the relief office, I'd seen my people.
As they stood there hungry, I stood there asking,
Is this land made for you and me?

Of course the irony is that when it got published and covered they leave off the last couple verses and it basically comes out as a song just like "God Bless America"