A 10% drop is deemed a correction by professional investors, and the S&P 500's 1.4% slide on Thursday sent the index to its first since 2023. The losses came after Trump upped the stakes in his trade war by threatening huge taxes on European wines and alcohol. Not even a double-shot of good news on the U.S. economy could stop the bleeding.

A 10% drop is a big enough deal that professional investors have a name for it — a “correction” — and the S&P 500’s 1.4% slide on Thursday sent the index to its first si