Santoli: Stocks enter fourth quarter playing offense

A stock chart is displayed on a terminal as traders work on the floor of the New York Stock Exchange.
Daniel Acker | Bloomberg | Getty Images

The headlines are enough to keep any investor in a defensive crouch—a vicious presidential campaign, Federal Reserve policy in constant flux, Deutsche Bank wobbling uncomfortably near the center of the world's financial system.

Yet a careful look at the stock market itself shows that it's transitioning subtly toward an offensive footing.