NEW YORK — Soldier of Fortune magazine today released its annual “Soldier of Fortune 500” index, honoring the 500 best-armed corporations in America.

“Our economy is the strongest it has been in 20 years,” President Clinton wrote in a special introduction. “Unemployment is down, profits are up and the stock market has hit an all-time high. But how well are our corporations prepared to fend off an armed assault, or initiate one if necessary? Each year, Soldier of Fortune does this country a valuable service by identifying those American companies that are best prepared to compete in the global arena, militarily as well as financially.”

There were some surprises. Consumer-goods manufacturer Ralston Purina jumped up from #22 to #8 after equipping its St. Louis headquarters with an underground bunker stocked with two years’ rations. McGraw-Hill’s aggressive new hiring strategy, offering large bonuses for employees versed in sniper tactics, catapulted the publisher into the #6 slot.

But once again, for the fourth straight year, pharmaceutical giant Merck tops the list. Their Whitehouse Station, NJ compound houses both their corporate operations and their vast storehouse of weapons, which includes 15,000 assault rifles, 20,000 hand grenades and five authentic German Panzer tanks. Every day, Merck employees have to swim to work across a rapid river with serrated hunting knives clenched between their teeth.

“On behalf of the employees, directors and shareholders of the Merck Corporation, I’m proud to accept Soldier of Fortune’s award as the best-armed company of 1997,” said Merck CEO Don Pendleton, who won the company’s top position two years ago in hand-to-hand combat. “I know that there are lots of other well-armed companies out there, and to the CEOs of those companies I extend the following message: I am coming to kill you in your sleep.”

“Merck’s a tough competitor,” said Soldier of Fortune editor James Graydon. “When Bristol-Myers Squibb was developing an anti-cholesterol drug called Doxamed, three Merck operatives came down a zip line and cut their researchers’ throats. Just before they clutched onto a Merck helicopter and flew to safety, they used the victims’ blood to smear a single word: ‘Doxa-Dead.’ Those guys are professionals.”

There are up-and-comers, however. Besides Ralston and McGraw-Hill, Graydon points to some other companies who might be positioned to challenge Merck in a few years.

Ketchup-maker H.J. Heinz, for example, has implanted cyanide capsules in all of their employees’ cheeks, with instructions to break them if they are ever imprisoned by Hunt’s mercenary death squads. Financial software provider Intuit has built a special Idaho compound in expectation of a coming civil war, where heavily armed software engineers are developing a version of their product that is “race-war compliant.”

Smaller corporations are preparing to compete in this arena as well. Stock in multimedia designer North Communications recently jumped $8.50 a share on news that a commando team had liberated four attack helicopters, equipped with ground-to-air missiles and stealth technology from rival Lexitech, Inc.

“Air superiority is the future of corporate competition, and our stockholders understand that,” said North president Paul Kennedy. Asked for a response to Lexitech’s pending lawsuit charging unfair business practices, Kennedy brandished a necklace of human ears aloft at a press conference and threatened to bayonet the children of Lexitech executives if the suit was not dismissed.

“For better or worse, the placid, white-collar corporate environment is going the way of the dodo,” said Stanford economist Paul Krugman. “Corporate skyscrapers have given way to military compounds, and the suit-and-tie has been replaced with desert camouflage. These days, job-seekers should forget about the size of a company’s headquarters and focus on how many heads are mounted on the gates outside.”