The Great Depression was caused by several things, but compound interest and other things that the credit industry finagled to get the most money out of their consumers was a definite cause. After the Great Depression, credit cards had much more strict regulations, much more.
"Post War Era" I'm assuming meaning post-WWII, if so following WWII consumer borrowing had much stricter regulations in correlation with credit cards, as people could borrow or purchase things they couldn't afford and pay it off with a credit card.