Petroleum Geologist Art Berman Explains How Not Every Barrel of Oil Is Equal.

Why It Matters

The distinction between light and heavy crude creates a strategic vulnerability: without sufficient diesel supply, transportation, logistics and industrial activity could be sharply disrupted, limiting economic resilience even as crude exports rise. Policymakers and markets must account for product quality and refinery capability, not just crude volume, when assessing energy security.

Summary

Petroleum geologist Art Berman argues that not all barrels of oil are interchangeable: the U.S. exports about 4 million barrels a day of light crude but imports roughly 6.5 million barrels of heavier crude that yields diesel and other middle distillates. Light oil produced domestically is ideal for gasoline and petrochemicals but lacks the molecular components to make diesel, which means the country remains dependent on foreign sources for that fuel. Berman emphasizes diesel’s outsized role in the global economy—powering ships, trains, trucks, farm and mining equipment—and warns there are no scalable near-term substitutes. That structural mismatch leaves the U.S. a net importer of a strategically critical refined product despite being a major oil exporter.