Dhaka, May 1 -- Right now, oil investors' main obsession is excessively high prices. Fair enough: the effective closure of the Strait of Hormuz since early March has sent Brent crude as high as $126 a barrel. Even so, the United Arab Emirates' departure from the Organization of the Petroleum Exporting Countries this week may still mean that the market's most striking feature in the next few years is not too little supply, but too much.

Prices are now way above their $90 a barrel mid-April level because the world's 8 billion-plus barrels of crude and product reserves are rapidly diminishing and unevenly distributed. Moreover, despite a ceasefire between Iran and the United States, it's far from clear that the status quo will last. With bo...