WHEN IT COMES TO gallows humor, you can't get much more hilarious than nuclear war.

It's the ultimate downer, after all. So it's not surprising that people respond with the ultimate defense mechanism. Dr. Louis Borgenicht calls it "nuclear humor."Borgenicht is a Salt Lake pediatrician and a member of Physicians for Social Responsibility, a national organization of 60,000 doctors working to eliminate the threat of nuclear holocaust.

It was while he was traveling around Utah giving serious talks about the medical dangers of nuclear war that Borgenicht realized that what the world needs, in addition to global peace of course, is something to laugh at. Humor, he noticed, not only is an outlet for fear, it also makes the anti-nuclear movement more understandable.

People will only listen so many times to details about how a nuclear winter will wipe out the human race. A good joke, on the other hand, makes them think about the threat in a new way.

Borgenicht, who had been collecting nuclear humor for several years, decided to gather all his material together into a multimedia extravaganza, which he presented at the annual convention of Physicians for Social Responsibility last month.

The response was so favorable - the San Francisco Examiner described the event as "open mike night at Armageddon" - that Borgenicht has been asked to repeat the performance in Philadelphia and Washington, D.C.

He will also present the show - "The Last Laugh: Nuclear Humor" - in Salt Lake City at 8 p.m. April 17 in the Utah Media Center, 20 S. West Temple. Tickets are $3 (a tax-deductible donation).

The show features cartoons, stand-up comedy, political commentary, bumper stickers, parodies and film clips. But some of the funniest stuff, says Borgenicht, comes from real life.

He points to a news article that appeared in the Deseret News in 1982 outlining the government's plan for crisis relocation - a detailed scheme to move residents of high-risk areas to rural sites, in advance of an atomic blast. The article notes that the plan "assumes a week's notice of a nuclear attack."

"If you take verbatim the government's plans for survival or crisis relocation," notes Borgenicht, "it's absolutely hysterical."

One of his favorite government documents is a plan detailing how to get emergency change-of-address cards to nuclear survivors.

The doctor (who bills himself as "the explosive Dr. Lou Borgenicht") has no scarcity of material to choose from, he says. People are now sending him cartoons and news clippings from around the country - reporting such new developments as the recent Internal Revenue Service plan for collecting taxes in the event of nuclear attack.

"The one way I've always dealt with anxiety is to make a joke of it," explains Borgenicht. "And certainly one of the biggest anxieties facing the world today is nuclear war."

*****

(Chart)

Nuclear humor/nuclear bombs?

QUESTION: What happens when a neutron bomb explodes in a dirty kitchen?

ANSWER: The nagging is gone but the dishes remain.

Here's a joke circulating in Russia:

QUESTION: What's the Russian word for Civil Defense?

ANSWER: Coffin.

From a 1981 Federal Emergency Management Agency film:

"Nuclear war is survivable. . . . In a full-out nuclear war, only 5 percent of the nation's land area would be affected by a nuclear blast. . . . Of course, that 5 percent contains a large percentage of the population."

Or as Woody Allen says: "More than at any other time in the history of mankind we face a crossroads. One road leads to despair and utter hopelessness, the other to total extinction. I just pray we have the wisdom to choose correctly."