Last time the Left had the people in any significant numbers and the capital was on its knees was during the New Deal. They should have moved for the kill back then instead of letting the beast survive and grub itself on the WW2 profits. After McCarthy - it was mostly the elite driven progress in response to competition from the USSR. It is not that the Civil Rights and ant-war movement were unimportant, but that they would have not succeeded had it not been for the political support of the more enlightened parts of the oligarchy.
Wojtek