How and why did the Great Depression change liberal notions operating in the world economy of the 1920?

For starters, all of the major currencies left the gold standard during this time period, which aided recovery. Most countries also shifted to variations of the mixed economy with much more government involvement in the economy. This is in stark contrast to the liberal laissez-faire economic policies before. The severity of the Great Depression caused governments and economists to rethink global and local economic policies.