THE UNITED STATES WAS ONCE a major whaling nation, but its involvement ended in 1972, when the last U.S. whale-processing station closed in Richmond, California. A decreasing demand for whale oil, the dwindling supply of whales brought on by overharvesting, and a vocal environmental movement put a stop to an industry that had thrived in America since colonial times. That same year, the United Nations passed a resolution calling for a halt to all whaling, and President Richard Nixon signed the Marine Mammal Protection Act, banning commercial whaling in U.S. waters.

Worldwide, whaling is an ancient, widespread practice, with indigenous populations from Indonesia to Siberia taking part. Though the U.S. government opposes commercial whaling, it still allows Alaskan tribes to kill dozens of bowhead whales annually—even though bowheads are an endangered species.

These days, most Americans don't approve of whaling in any form, though their reasons are often based more on emotion than facts. Richard Ellis, a 68-year-old research associate with the American Museum of Natural History, in New York, and author of Men and Whales, a sweeping 1991 history of whaling, says nations like Norway probably have a point when they argue that, for certain species such as the minke—which was rarely hunted for oil, because of its smaller size—numbers are healthy enough to sustain managed hunts.

But he's against killing whales anyway, in part because he doesn't think we know enough about the balance of ocean systems to be sure any species is numerous enough to be hunted. In part, though, it's a gut feeling. "You'll never convince Norwegians not to hunt whales, and that's not the end of the world," he says. "But I just don't think they ought to be killed."

To Norwegians, whaling is utterly normal. People in Norway's coastal communities started killing them during the Stone Age, and today many of the nation's two million households still enjoy this $10-a-pound meat on special occasions. Currently, Norwegian fishermen restrict themselves to one relatively plentiful species: the North Atlantic minke whale, Balaenoptera acutorostrata.

Called vågehval ("bay whale") in Norwegian, minkes are handsome mammals—shiny black on top, snow white on the underside—that can live for 50 years. They're baleen whales, meaning they feed by pushing huge gulps of water through anatomical sifters that capture krill and fish. They winter in tropical southern latitudes, but no one knows where exactly. Come spring, they migrate north along Norway's coast to gorge in its Arctic waters. Greenpeace, which strongly opposes Norway's whale hunt, estimates there are approximately 67,000 minkes in the North Atlantic. (No one knows the total, but there are many more minkes in the Southern Ocean waters circling Antarctica.) Norway's approximately 150 whalers, who catch cod and other fish the rest of the year, killed a total of 639 minkes during the 2005 season, which ran from April to October.

Though Norwegian whaling is carefully controlled, it wasn't always so. In the 19th and 20th centuries, industrial nations like Norway, the U.S., Russia, and Japan took several species to the brink of extinction. An estimated five to ten million whales swam in the world's oceans before hunting went big time, starting in the 1860s. The industry eventually decimated stocks to a few hundred thousand and almost wiped out entire species, such as the blue, humpback, and right whale. Of the world's 37 or so species, nine are still endangered, and it remains unclear whether the blue whale—at up to 150 tons the largest creature that's ever lived—will ever rebound.

In 1982, a worldwide moratorium on whaling was decreed by the Cambridge-based International Whaling Commission (IWC), a governing body created in 1946 to set policies that were designed to conserve falling stocks while hunting continued. Norway, Japan, Iceland, and various native groups in Alaska, Siberia, Greenland, the Caribbean, and the South Pacific still kill whales. Many governments and private environmental groups—most notably Greenpeace and the Sea Shepherd Conservation Society—want the big industrial nations to stop.

But the 66-nation IWC lacks an enforcement arm, which sets the stage for the intractable disputes we see today. As a result, the IWC, which will hold its 58th annual meeting from May 23 to June 20 in St. Kitts and Nevis, West Indies, has essentially been reduced to managing a stalemate.

Norway says its hunts are perfectly legal. It was one of four countries from the IWC charter group of 16 nations that didn't endorse the '82 moratorium. By 1992, when Norway resumed whaling after a one-year hiatus, the country had long since scaled back its industrial whale slaughter and was killing only a small number of minkes every year. The Norwegian government introduced a new system of quotas, and whaling was reborn as a supplemental income source for the fishing fleet.

Japan later signed on to the IWC moratorium but has continued killing whales—the country will take approximately 850 minke and ten fin whales in 2006—under the pretense that the animals are being collected for scientific research. Meanwhile, whale meat and blubber can still be found in Japanese markets.

Iceland resumed whaling in 2003 as well. But whereas Norway and Iceland hunt within their own borders, Japanese whalers still work in international waters, and that means its six-vessel "research" fleet is subject to serious high-seas interference. Last December and January, boats from Greenpeace and Sea Shepherd caused weeks of mayhem for the Japanese fleet in the Southern Ocean, with Greenpeace members acting as human shields trying to thwart the whalers and Sea Shepherd's captain, Paul Watson, using his ship Farley Mowat as a floating weapon to sideswipe the hulls of Japanese boats.

Norway has weathered spirited protests over the years but draws less attention by hunting close to home. Government officials and whalers there, however, make it clear they'll do what they want. The High North Alliance, an advocacy group based in Norway's Lofoten Islands, publishes a newsletter, The High North News, that mocks the Western world's supposed hypocrisy about whales and proclaims Norway's hunt to be the best example going of "conservation in action."

Currently, both the Norwegians and Japanese seem determined to increase their kills. Norway is raising its minke whale take to 1,052 animals this year and will allow the fleet to hunt in international waters. When asked if Norwegian whalers would like to start taking larger species, Rune Frøvik, the director of the High North Alliance, told me, "They're definitely interested in that."