The aerospace and defense sector is trading lower, with the ITA ETF down over 2%. A significant contributor to this decline is a 3% drop in Boeing's stock (BA) after a software glitch on its 737 MAX drew regulatory scrutiny. This company-specific news is weighing on the broader sector. Additionally, overall market sentiment is negative, with the Nasdaq and S&P 500 falling due to renewed U.S.-Iran tensions and a rise in oil prices, contributing to the downward pressure on defense stocks.