President Trump has a tendency to announce major developments over weekends, compelling Wall Street to readjust its strategies. Last Saturday, Trump declared that Iran had 48 hours to reach an agreement or face a series of devastating attacks targeting public utilities and other infrastructure. However, by Monday, he reversed course, announcing a five-day suspension of strikes on energy facilities. Following the news, Brent crude oil fell by more than 14% at one point during Monday's trading session.

On Thursday, after U.S. stock markets had closed, Trump extended the deadline to April 6. Spot crude oil prices initially turned negative and risk assets briefly rebounded, but markets appeared to grow increasingly "immune" to Trump's verbal interventions, with asset prices eventually reverting to their intraday trends.

By Friday, as tensions escalated further, U.S. crude had recovered all of its weekly losses. U.S. stocks experienced a sharp decline during the week, with the Dow Jones Industrial Average falling more than 10% from its yearly high, joining the Nasdaq in correction territory.

Trump's series of announcements during market closures have had a tangible impact on trading behavior. Traders across equities, fixed income, and commodity markets are increasingly reluctant to hold large positions heading into the weekend, seeking to avoid potential volatility at Monday's market open.

Kathy Jones, Chief Fixed Income Strategist at Charles Schwab, commented this week that entering the weekend with any significant position could lead to a very difficult Monday morning.

Weekend announcements have become a recurring pattern. A review of Trump's recent actions shows a preference for taking major steps on Saturdays. Last June's airstrike on Iran, this year's forceful measures against Venezuelan President Maduro, and the latest military actions against Iran all occurred on Saturdays or over weekends, when major markets, including foreign exchange, are closed.

White House spokesperson Kush Desai denied any connection between the timing of military actions and market closures, stating in an email that it is absurd to suggest operations are scheduled around stock market hours rather than intelligence and operational effectiveness. An unnamed White House official also reportedly described the frequency of major weekend announcements as coincidental.

Nonetheless, Trump's inclination for dramatic moves, often timed outside market hours, has reshaped the dynamic between Wall Street and Washington. As the prospect of closing the Strait of Hormuz becomes more real, his ability to calm markets with optimistic rhetoric is diminishing. Even a 10-day suspension of military action offers no guarantee of stability.

A Deutsche Bank analysis indicates that Trump tends to make his most impactful decisions when market stress is highest. The bank's "stress index," which incorporates the S&P 500, U.S. Treasury yields, inflation expectations, and Trump's approval rating, has reached its highest level since he took office in January 2025. Previous peaks coincided with Trump delaying "reciprocal tariffs," clarifying that he would not fire Fed Chair Powell, and threatening not to use force in acquiring Greenland.

Evidence also suggests that Trump's weekend announcements significantly impact Monday's market open. Gaps between Friday's close and Monday's opening prices for EUR/USD and the S&P 500 are becoming more frequent, leaving investors little time to close losing positions.

Despite the recent pause, the market remains uncertain about what comes next. Wolfe Research analyst Tobin Marcus labeled Trump's latest move a "Schrödinger's TACO" and warned in a Monday report that as Trump deploys Marines to the region, the risk of escalation remains high, including the potential seizure of Iran's key oil export hub, Kharg Island.

Marcus noted that once forces are in place, Trump will face a difficult choice: de-escalate, escalate, or maintain the status quo. He emphasized that investors must take the possibility of escalation seriously.

Trump's mixed signals on Middle East tensions have drawn criticism. Former Deputy Secretary of State Wendy Sherman suggested that the pause may be a stalling tactic until troops are deployed, warning that a prolonged standoff would prevent the president from manipulating markets every Saturday and Monday.

Josh Lipsky, Director of the Atlantic Council's GeoEconomics Center, urged caution, advising markets and the public to expect increased weekend volatility going forward. He also warned against overinterpreting any perceived patterns in Trump's behavior.