On April 17, 2026, in New York City, traders are actively engaged on the New York Stock Exchange floor during the morning trading session.
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On Sunday evening, stock futures declined sharply following heightened weekend tensions between the U.S. and Iran, triggered by the confiscation of an Iranian-flagged cargo vessel.
Futures for the Dow Jones Industrial Average fell by 452 points, representing a 0.9% drop. Meanwhile, S&P 500 futures saw a decrease of 0.8%, and Nasdaq-100 futures retracted by 0.6%.
On Sunday, President Donald Trump announced that the United States had opened fire on and subsequently impounded an Iranian-flagged cargo vessel within the Gulf of Oman. This incident occurred after Iran opted not to participate in a new series of U.S.-arranged peace discussions slated for Pakistan.
In a post on Truth Social, Trump stated, “The Iranian ship is subject to U.S. Treasury Sanctions due to its previous record of unlawful conduct. We currently have complete control of the vessel and are assessing its contents.”
Furthermore, Trump issued a threat, warning that the U.S. would destroy all of Iran’s power plants and bridges if the nation failed to agree to a pact. A current ceasefire between the two nations is set to conclude this week.
Early trading saw a significant increase in crude oil prices. Futures for West Texas Intermediate climbed by 8%, reaching $90.54 per barrel, while International Brent rose by 6% to hit $96.50.
Wall Street had just concluded a successful week, where both the S&P 500 and Nasdaq Composite achieved record highs after a ceasefire agreement between Iran and Lebanon. During that period, Iran had announced the reopening of the Strait of Hormuz; however, by Saturday, shipping activity through the vital waterway was once again curtailed, with Iranian state media claiming the U.S. “did not fulfill their obligations.”
Despite Iran’s earlier announcements, Trump reaffirmed that the U.S. blockade of the strait would persist until Iran conceded to American demands.
Last week, the S&P 500 rose by 4.5%, and the Nasdaq Composite surged by 7.2%. Additionally, on Friday, the Nasdaq marked its 13th straight day of gains, a winning streak unprecedented since 1992.
In an email to CNBC, Peter Boockvar, chief investment officer at OnePoint BFG Wealth Partners, commented, “Following the Nasdaq’s 13-day consecutive rally fueled by deal hopes, we concluded the week in a significantly overbought short-term state. The situation with Iran has now become even more complex and unpredictable regarding when this conflict will cease and when the Strait can fully reopen without threat of aggression.”
He further questioned, “Assuming there are no new developments, the sole inquiry for Monday’s trading will be the magnitude of the market’s correction?”