Keynesian ideas were dominant in the U. S. from the mid-1930s through the 1970s, yet during that time the national debt increased steadily rather than going up and down. Why do you C
think the application of Keynesianism resulted in increasing deficits rather than a movement
back and forth between deficits and surpluses as Keynes recommended?

Explanation:

Entitlements.

The government increased its obligation to students, to homeowners, to those on social security, to Medicade and Medicare, to all sorts of programs that needed money.

War

Wars were increasingly becoming more expensive. In 2010 the United States was supposed to have paid off the Vietnam war. I think they did achieve that, but they fought some wars in between. Iraq (twice) Afghanistan,  These wars were not cheap. The debt grew. The only recent prsident who tried to do anything about was Clinton.

c. the passage of the fifteenth amendment