Could the EU's weaker countries e.g. Greece first cause an EU crisis which in turn causes a global downturn?

Today the USA markets are 'concerned about Greece affecting the EU ' and markets are lower as a result. If the west is affected this will affect eastern markets as well. I can see clearly in the financial news how the lack of success of sometimes small countries can have such a global knock-on effect.Where can I read about this level of economics?