Social democrats and the step-to-the-left deomcratic socialists, are completely dependent on capitalism to deliver growth and investment. Hooked without reserve on the stream of taxes which flows from capital.
America on the other hand is a land where capitalism is dependent on social democracy and mechanisms of protectionism and how shall we put it, market access vi the gun and the might.
Capitalism of course by in large is not hooked on democracy, having actually managed to buy it as a brand name for mis-use some time ago. Without social democracy to temper, it is a pretty horrid place.