S&P 500, Nasdaq, Dow futures fall as Trump rejects Iran peace proposal

U.S. stock index futures dropped sharply on Monday evening after President Donald Trump rejected an Iranian peace proposal, reigniting fears of a broader conflict in the Middle East.

S&P 500 futures slid 1.2%, while Nasdaq 100 futures lost 1.4% and Dow Jones Industrial Average futures fell 1.0%. The move came after reports that Iran had put forward a diplomatic initiative to de-escalate tensions, only for the White House to dismiss it outright. Geopolitical risk is a classic headwind for equities, as uncertainty over energy supplies and regional stability tends to compress valuation multiples. For context, the S&P 500's forward P/E ratio had been hovering near 21x, above its 10-year average of 18x, leaving the market vulnerable to shocks. The earnings yield on the S&P 500 now stands at roughly 4.8%, while the 10-year Treasury yield is around 4.2%, narrowing the equity risk premium. A further spike in oil prices could squeeze margins and push the Fed toward a more cautious stance. Traders can track the live reaction in U.S. index futures on NowPrice's real-time stocks dashboard. The energy sector, in particular, may see outsized moves given Iran's role in global oil markets. Sector rotation has already begun, with defensive utilities and healthcare gaining relative to cyclicals, while buyback yields—currently near 3.5% for the S&P 500—may offer some support if volatility remains elevated.

Looking ahead, market participants will focus on any further diplomatic signals from Washington or Tehran. A lack of progress could push crude oil prices higher, adding to inflationary pressures and complicating the Federal Reserve's policy path. Key technical levels on the S&P 500 — such as the 200-day moving average — will be closely watched as support. Breadth indicators, like the percentage of stocks above their 50-day moving average, have already deteriorated to around 40%, signaling a narrow market. Options-implied volatility, as measured by the VIX, has spiked above 20, reflecting heightened hedging demand. Any escalation over the coming days could trigger a broader risk-off rotation out of equities and into safe havens like gold and Treasuries.