Throughout history, we were trained to believe that quantitative easing would result in a bullish stock market due to the deflation of a currency. It has been like so in the recent cases of US market as well as Japan somewhat. With that said, many believe that a weaker Euro would also have a direct effect upon US equities through the increased difficulties of exporting goods. If the European QE causes the Euro to drop further, then European exports would become much cheaper for buyers in the US, but our exports would become much more expensive. As the stronger US dollar has been making it hard and less profitable for our exporters, our businesses would certainly feel the effect and thus, causing a bearish stock market.