Will an Upbeat Federal Reserve Burst the Market Bubble?

It's pretty clear by now just how dependent the global financial system is on the largesse of the world's central banks. The Federal Reserve, in particular, has taken on immense importance in the post-crisis world of ultra-low interest rates, aggressive stimulus measures and constant stock market activism. After all, fundamentals seem to matter less and less (witness the five-quarter long U.S. corporate earnings recession and stretched stock valuations) while stimulus matters more and more.