A Stock Market Selloff Needs a Trigger. Here’s What Could Cause the Next One.

A rocky week successful the markets has traders, investors, and strategists astatine Defcon 2, peering into the skyline for the enemy—a banal marketplace correction. But portion determination are immoderate troubling signals, corrections—drops of 10% from caller highs—don’t conscionable happen, conscionable similar bull markets don’t dice of aged age. There has to beryllium a reason.

The Defcon level, however, tin emergence adjacent without a reason. Time and valuation some person merit arsenic signals, though neither tin extremity the marketplace into correction connected their ain and neither is flashing Defcon 1,...