U.S. stock futures were mixed Tuesday as investors returned from the Labor Day holiday to stronger-than-expected August employment data, rising oil prices, higher bond yields and renewed concerns that the Federal Reserve could raise interest rates next week. Dow Jones Futures fell 0.8% to 53,013 points, while S&P 500 Futures slipped 0.3% to 7,691.3 points and Nasdaq 100 Futures were flat at 29,593 points. Investors were also awaiting the weekly ADP Employment Change report, based on a four-week moving average of private-sector employment, and a Treasury auction of three-year notes. The auction will offer a reading on demand for U.S. government debt as global bond markets remain under pressure and the national debt exceeds $40 trillion. Higher Treasury yields increase government borrowing costs and can raise mortgage rates, corporate financing costs and stock valuations, potentially weighing on companies dependent on future growth. President Donald Trump called for an immediate end to Bombardier sales in the United States, a market accounting for more than half of the Canadian aircraft maker's revenue. With Bombardier expected to generate about $10.2 billion in 2026 revenue, the threatened U.S. exposure could represent roughly $5 billion in annual sales. Geopolitical risks also increased after Iran threatened a maritime exclusion zone across the Persian Gulf in response to what it called U.S. economic warfare. Attacks by Iranian-backed Houthi forces on Saudi Arabia added to concerns about regional energy infrastructure and shipping. Brent crude rose 1.4% to a six-week high, moving closer to $100 a barrel after recently trading near $99. A sustained break above $100 could deepen inflation concerns, support expectations for higher rates for longer and pressure rate-sensitive technology and growth stocks, while benefiting energy producers.