Why would theorists and policymakers from different regions potentially approach IPE differently from one another?

Any thoughts? It is said that Marxism is very common in developing countries. In the developed world, we are seeing the protectionism approach becoming more popular. Why do theorists and policymakers from different regions approach the International Political Economy with different opinions? How can I elaborate on this question?

Thanks for your help,

Thomas.

http://www.google.com/#q=International+Political+Economy+&*