FWIW, Christina Romer has presented a reasonable argument that the degree of stability of the US economy before 1929 was not significantly lower than that after 1945. (It's an empirical argument, based on recalculating recent data so that the recent data are consistent with those of before 1929. The story changes if you include the 1930s.)
-- Jim Devine "Come back next Thursday with a specimen of your money." -- G. Marx.