One partial test of this would be to trace sources of political funds during periods of stress (say 1965-75). Were capitalists (esp. rentier capitalists) becoming more involved in financing political activity. Were there changes in the political spending of those who had traditionally supported Eisenhower, Stevenson, Rockefeller, etc.?
Control of the mideast has been central to u.s. policy for 60 years, and the ruling class has rallied around that policy (in both active and passive ways). A change in that strategy would be prefigured by more active participation by more members of the capitalist class, including, as I say, even the Paris Hiltons. ???
Carrol
Plato argued that no ruling class ever lost power as long as it remained unified. For left political thinking we should assume ruling class unity unless we are seriously predicting the development of a pre=revolutionary situation.