James Carville

Why Trump has little influence on rising or falling stocks

For months, President Donald Trump boasted about having steered the U.S. stock markets to record high after record high.

What a difference a few days can make.

The market free-fall, explosive volatility and now partial recovery of stock prices have served as a stark reminder that Trump, like his predecessors, isn't commander in chief of the U.S. economy — or the financial markets. The markets pivot on forces that owe at least as much to computerized trading programs, overseas investors and global central banks as they do to a president's policies and force of personality.

The Dow Jones industrial average went on a wild ride Tuesday — ricocheting between losses and...