U.S. stock index futures experienced a significant decline of over 1% on Monday, reflecting investor concerns about the escalating Middle East conflict and its potential to disrupt global trade and fuel inflation. Airlines were particularly hard-hit, with carriers like Delta and United Airlines seeing premarket drops exceeding 5% as flights were halted and crude oil prices surged 8%. Financial stocks also suffered, with major banks such as Bank of America and Citigroup falling over 2%. Conversely, safe-haven assets like the dollar and precious metals saw increased demand, benefiting miners like Gold Fields and Barrick Mining, while defense stocks, including Lockheed Martin and RTX, experienced substantial gains. The conflict's potential duration, with U.S. President Donald Trump suggesting it could last weeks, contributed to market uncertainty, exacerbated by existing worries about AI disruption and the private credit space.