Predicting "When will Trump end the war"? These are the five key points.

Ask AI · How the war’s end time will influence global oil price trends?

The Iran war has become the strongest geopolitical shock to the global energy market since the 1990 Gulf War.

Since the Iran war began on February 26, 2026, Brent crude has surged 44% in just 25 days, U.S. gasoline wholesale prices (Rbob) have risen 48%, U.S. diesel prices have increased by 51%, and European diesel prices have climbed by 58%.

Barclays Capital’s latest research report warns: When the war ends will directly determine whether crude prices revert to the $85 per barrel base case scenario or break above $110 per barrel. For investors, the five key catalysts currently driving how the energy market is priced are: the progress of military objectives, the budget power struggle in Congress, U.S. military casualties numbers, gasoline retail prices, and Trump’s personal judgment.

Barclays believes that oil price movements will diverge at three key time nodes: If the Strait of Hormuz returns to normal passage in early April, Barclays will keep its 2026 Brent crude average forecast at $85 per barrel; if it is delayed until late April, the average may be re-priced to around $98 per barrel; if it drags into late May, the average could reach $111 per barrel. With each day of delay, the accumulating inventory shortfall will transmit backward through a snowball effect, pushing the price center of gravity higher.

Five key factors: the core variables that determine the war’s endgame

Barclays public policy analyst Michael McLean outlines five potential catalysts that could bring an end to the Iran war:

Key point one: Military objectives achieved

According to CCTV News, the U.S. previously set out three objectives for Iran: to destroy Iran’s ballistic missile and drone capabilities; to strike Iran’s navy to maintain passage through the Strait of Hormuz; and to destroy Iran’s military and industrial infrastructure, causing it to lose the ability to launch external attacks for many years.** Notably, the objectives do not include regime change or Iran’s nuclear program.**

At the outset of the war, President Trump estimated that the operation would last “four to five weeks.” The war is now in its third week, and according to the White House’s wording, it may already be at a mid-point.

However, based on the number of targets being struck, there has not been a clear turning point indicating a drawdown in activity by U.S. Central Command; additional forces are still being deployed. Iran’s ballistic missile and drone attack frequency against the United Arab Emirates, Kuwait, Saudi Arabia, and Bahrain has fallen substantially, but has not fully stopped, indicating that Iran still retains some offensive capability.** Barclays believes that until the relevant indicators fall further, it cannot be concluded that the military objectives have been achieved.**

Key point two: Constraints from Congress—the War Powers Resolution creates a hard deadline of May 31

** The War Powers Resolution requires that within 60 days of deploying armed forces and submitting a report to Congress, the president must obtain congressional authorization (AUMF). The president may extend it by an additional 30 days, and after the 90-day period expires, military action must be forcibly terminated. Trump submitted the report on March 2, which implies that the 90-day hard deadline is May 31.**

In the Senate, the AUMF needs 60 votes to pass, and the Republicans currently hold only 53 seats. The Democrats have made their stance clear by voting on two resolutions of disapproval—therefore, it is highly unlikely that the AUMF will be approved; May 31 is the institutional hard boundary for the war’s end.

The war’s economic costs are also accumulating quickly: the first week cost roughly $11 billion to $12 billion, and the current average daily operating cost has fallen to about $500 million; through now, the estimated total spending is approximately $21 billion.

For comparison, the Iraq war’s nominal cost over 13 years was $815 billion; the total defense discretionary spending for FY2026 is $839 billion. In addition, One Big Beautiful Bill has pre-allocated $150 billion to the Department of Defense, which is currently providing some funding buffer.

Key point three: Rising U.S. military casualties will further erode public support

Barclays says that support for the war within the United States is exceptionally fragile and shows clear partisan division.

As of March 22, RealClearPolitics polling averages show: the approval rating is only 41%, while the disapproval rating is 49%. President Trump’s overall approval rating has inched down from 43% to 42%, the lowest mark of his second term (his lowest in the first term was 37% in December 2017).

There are already 13 U.S. service members who have been killed.

Historical experience suggests that wars often bring a “rally-around-the-flag” effect, briefly boosting presidential approval ratings, but Trump has not received that effect. The general rule is: the longer the war lasts, the higher the casualties, and the more pessimistic the public is about prospects for victory, the stronger anti-war sentiment becomes.

Key point four: Gasoline prices hitting a “political red line”—$5 per gallon is the key threshold

In July 2022, during the Biden administration, the nationwide average gasoline price peak was $5.01 per gallon.

For Republicans, staying below this “Biden peak” is a political psychological line of defense, corresponding to an implied WTI oil price of about $120 per barrel—over 20% higher than current levels.

At present, Republican officials still hold a relatively optimistic view, believing that even if oil prices face short-term pressure, there is enough time to fall back as the war ends before Labor Day (when investors truly start focusing on the midterm election). The administration has also taken a series of measures to try to ease oil price pressure, including releasing strategic reserves and waiving related sanctions.

Key point five: Trump’s proactive shift toward “declaring victory”

Barclays believes that regardless of the real progress on the battlefield, there is always a possibility that Trump could proactively declare victory at some point and end the war. When previously asked how to judge when the war ends, Trump’s answer was telling—“when I feel it in my bones.”

Barclays has made it clear that the timing of this catalyst is nearly impossible to predict.

In communications with clients, one mainstream analogy is that Trump’s earlier policy pivot after his “Liberation Day” (tariff announcement on April 2, 2025) has conditioned investors to believe that a market plunge could drive him to shift course.

But Barclays believes the market’s reaction now isn’t “panicked” enough: after Liberation Day, the S&P 500 fell by about 12%, whereas since this war began it has fallen by only about 5%; after Liberation Day, the yield on the 10-year U.S. Treasury jumped by 60 basis points, while in this case it rose by only about 40 basis points; investment-grade credit spreads widened by 26 basis points after Liberation Day, while in this case the peak widening was only 9 basis points. More importantly, pausing a tariff executive order is far easier than ending a real war.

Oil price upside risk skews significantly higher

Barclays’ core view is that the current rise in oil prices is not a speculative bubble, but a reflection of a genuine imbalance between supply and demand.

Before the war, the historical fair value implied by Brent relative to OECD inventory levels was underestimated by about 19%, and relative to an alternative cost model was underestimated by about 15%; Brent and WTI net speculative long positions were at the second percentile of historical lows since 2014 by the end of 2025.

The evolving dynamics of the five catalytic factors—progress of military objectives, budget power struggle in Congress, U.S. military casualties numbers, gasoline retail prices, and Trump’s personal judgment—will be the most important high-frequency tracking dimensions for assessing the direction of the energy market next. Barclays has explicitly stated that under uncertainty, the risk to its 2026 Brent crude forecast of $85 per barrel is tilted upward.