ngdawg

Actually, that's not entirely true. Social Security was implemented in 1935 by FDR in response to the Great Depression-hardly a rapid social change. The Depression itself was a result of investors buying into stock with stock-as investors wished to cash in their options, lo and behold, there wasn't any money to be had and the stock market crashed.(short version).
SS itself was modeled after the Civil War Pension program, which paid to soldiers from that war.
To help the families left destitute by the Crash, Roosevelt implemented Walfare, also in 1935. Before then, families depended on local government, along with private charities, to help, but with over 13,000,000 people left penniless, it behooved Roosevelt to step in and create national programs. His first priority was, of course, to create jobs, but for those who could not work(children, the elderly or handicapped), these two social programs were a godsend.
I guess if you called the Crash of 1929 "social change", then the reasons for our government assistance programs would apply.

We aren't a nation of rapid social change. We are a stewing pot on medium heat that when left to heat a bit too long, boils over. Vietnam went on for almost 20 years before several years of protesting, the enormity of lives lost and the futility of it forced Washington to rethink it. Civil Rights came to a boil in the early 60's but was stewing for over 100 years before that.