Nasdaq Sets Record as AI Shares Offset Dow’s Drop

The Nasdaq Composite closed at a record 27,244.28 on Tuesday, September 22, up 0.5%, while the Dow Jones Industrial Average fell 0.4%, or 185 points. The S&P 500 edged down less than 0.1%, leaving the indexes split.

AI-linked shares helped the Nasdaq withstand weakness elsewhere. Micron Technology gained 5% and Sandisk rose nearly 7%, according to Reuters, extending a run of gains in chip stocks.

Meta Platforms also remained in focus after its new Muse AI assistant helped fuel Monday’s tech rally. Reuters reported that analysts highlighted strong early downloads for Muse, adding to investor interest in how AI products might generate new revenue.

Diplomacy offered a second market driver. Iran said it could reopen the Strait of Hormuz within seven days if Washington eased military pressure, Reuters reported. The waterway is a key route for global oil shipments.

President Donald Trump addressed the Iran conflict at the United Nations, warning of escalation while also leaving open the possibility of a deal. Brent crude briefly fell below $98 during Tuesday’s session, then settled at $99.25, down 1.1%, according to the Associated Press.

Oil remains well above its roughly $72 level before the conflict began. That leaves investors watching whether diplomacy can ease supply fears, or whether renewed tension pushes energy costs higher again.

The Dow’s decline reflected pressure on bank shares. JPMorgan Chase fell 3.4%, while the 10-year Treasury yield barely moved, ending near 4.95%, the AP reported.

Investors also looked ahead to a planned Trump-Xi summit later in the week, where trade and competition over AI are expected to feature. Any sign of a steadier U.S.-China relationship could shape expectations for technology companies and supply chains.