You could easily tell, why countries move to the left.
Why did Marx come up with his ideas?
They were an answer to Manchester capitalism, and some of those ideas had to be used by the European gouvernments to prevent a major uproar or revolution.
(a nice, but old read on this with Germany as an excample http://query.nytimes.com/mem/archive-free/pdf?_r=1&res=950DE4DD123FE433A25756C2A96E9C946696D6CF )
Why didn't this apply to the USA?
Less people in a bigger country, the basic for capitalism aka. growth was there all the time with more people coming in and still land etc. available for them.
The major questions are now: How long does this work and if the growth stops or slows down (if it hasn't already), how do you make sure to keep up the national security within the country.
I know, that this is somewhat simplified, but I hope it gives you some new views on this topic^^







