WASHINGTON/LONDON—Global share markets stumbled on Tuesday, rattled by disappointing U.S. retail sales data and a surge in COVID-19 infections worldwide driven by the Delta variant. Wall Street opened sharply lower as investors digested data showing U.S. retail sales fell more than expected in July, after global shares slid amid fears of stricter rules on the internet sector coming out of China. The Dow Jones Industrial Average fell 0.7 percent in early trading, while the S&P 500 lost 0.53 percent and the Nasdaq Composite dropped 0.65 percent. The MSCI world equity index, which tracks shares in 45 nations, fell 0.68 percent. The Commerce Department reported that U.S. retail sales fell more than expected in July, falling 1.1 percent as supply chain disruptions weighed on automobile purchases. While a rebound is expected as parents go shopping ahead of a return to in-person school in the fall, there is lingering concern that rising …