AI-related business investment is rapidly becoming a cornerstone of U.S. economic growth, marking a structural shift in how expansion is financed and sustained. In the first half of 2025, investment in information-processing equipment and software — largely driven by AI infrastructure — is a small yet mighty slice of the economy, yet contributed a majority to economic growth during that period.

The S&P 500 is over halfway through Q3 earnings season, and results have been impressive. Of the 318 companies that have reported results, 83% have surpassed earnings per share (EPS) estimates, notably above the 10-year average beat rate of 75%, according to FactSet.

With the stock market in record-high territory and up about 35% off the April lows, market participants clearly haven’t been too scared lately. But that doesn’t mean there aren’t plenty of things to worry about. Just because risks haven’t affected markets much lately — subprime auto loan bankruptcies notwithstanding — doesn’t mean they won’t in the future. In that “spirit,” as Halloween approaches, we discuss what scares us about the economy and financial markets.