The Brief

Wall Street’s “Great Rotation” has accelerated through mid-March, with the energy sector posting a 25 percent year-to-date rally — led by ExxonMobil, Chevron, and Occidental Petroleum — while the technology sector has slid roughly 5 percent and the Magnificent Seven have fallen 8.8 percent collectively. The divergence, driven by the Iran conflict’s disruption of Strait of Hormuz oil flows and a widening power-grid bottleneck stalling AI data-centre expansion, has pushed sector dispersion to the 99th percentile of historical norms.

The Report

The S&P 500 energy sector surged 25 percent through mid-March 2026, its strongest opening to a year since the commodity super-cycles of the early 2000s, while the technology sector declined approximately 5 percent in what analysts are calling the most aggressive sector rotation in modern market history.

The immediate catalyst is oil. Brent crude climbed from around $70 per barrel in late 2025 to an intraday peak of $119.50 during the week of March 8, after the U.S.-Iran conflict choked tanker traffic through the Strait of Hormuz — a waterway that normally carries roughly 20 percent of global oil and LNG supply. WTI crude recorded its largest weekly gain since the futures contract began trading in 1983, jumping 35 percent. Iraq’s production fell 70 percent, Kuwait announced cuts, and on March 11 the International Energy Agency agreed to release 400 million barrels from emergency reserves — more than double the 182.7 million barrels released during the 2022 Russia-Ukraine crisis, and the largest coordinated action in the agency’s history. Brent still closed the day higher, at $91.98, suggesting the market considers the release insufficient relative to the potential duration of the disruption.

ExxonMobil and Chevron are both up more than 25 percent year-to-date. Occidental Petroleum has gained over 30 percent. ExxonMobil has committed $27–29 billion in capital expenditure for 2026 alongside $20 billion in planned share buybacks — positioning that appears to price in sustained $100-plus oil despite J.P. Morgan’s base-case forecast of $60 per barrel. Goldman Sachs estimates a $13-per-barrel war risk premium above its $65 fair value, with risks “significantly skewed to the upside.”

The technology decline has a second, structural driver beyond the geopolitical shock. A 15 percent global tariff introduced in early February pressured hardware supply chains, but the deeper constraint is electrical. Morgan Stanley projects U.S. data-centre demand will reach 74 gigawatts by 2028 against a power-access shortfall of approximately 49 gigawatts. Microsoft and Alphabet have earmarked over $600 billion in combined capital expenditure for 2026, yet the grid cannot deliver the power to run what they are building. Microsoft’s market value has eroded 15 percent since January. Nvidia, despite 73 percent year-over-year revenue growth and a $78 billion first-quarter guidance, has fallen 5 percent as hyperscalers develop competing silicon.

The energy sector’s response to the AI bottleneck is already reshaping itself. Constellation Energy completed its $16.4 billion acquisition of Calpine Corporation in January, assembling 60 gigawatts of combined generation capacity. Its CEO called the merged entity a “one-stop shop for the global data economy.” NextEra Energy has secured contracts for over 2.5 gigawatts of clean energy capacity with Meta. Wall Street has reclassified these utilities from bond proxies to technology enablers, expanding their price-to-earnings ratios from historical levels near 15 to above 30.

Bank of America and Merrill Lynch have labelled the shift the “Bits to Atoms” transition. Eight of eleven S&P 500 sectors have reached new all-time highs in 2026, while the seven largest companies — which represent nearly 40 percent of the index — have collectively dragged it flat.

The Angle

The standard framing treats this as a rotation — capital moving from one sector to another, the way it periodically does, before moving back. The more precise reading is that the market has stumbled into a category error it spent three years ignoring. The AI buildout was priced as a software story. It is, at bottom, an energy story. Software scales at marginal cost approaching zero. Electricity does not. Data centres do not run on code. They run on gigawatts, and gigawatts are produced by turbines, fuel rods, and gas pipelines — objects that take years to permit, build, and connect. The companies that understood this — Constellation assembling 60 gigawatts of capacity, NextEra signing multi-year power purchase agreements — are being repriced not because oil spiked but because the spike made visible what was already structurally true.

The Iran conflict accelerated the repricing. It did not cause it. The 49-gigawatt shortfall Morgan Stanley projects by 2028 existed before a single missile was fired near the Strait of Hormuz. What the war did was remove the comfortable assumption that energy would remain cheap and abundant while the digital economy scaled on top of it. That assumption was never tested because it never needed to be — until a waterway carrying a fifth of global supply became contested and electricity prices had already climbed 6.9 percent in 2025 alone.

The IEA’s 400-million-barrel release is the detail worth watching. It is the largest coordinated intervention in the agency’s history, and the market’s response was to push crude higher. When the largest tool in the emergency kit is deployed and prices still rise, the signal is not about barrels. It is about the market’s assessment of how long the disruption lasts — and what the world looks like on the other side of it.

The infrastructure that was supposed to power the next decade of digital expansion turns out to require the century it was supposed to replace.