They told us Sept. 11 marked the end of irony in America.

The obituaries were written by hyperventilating pundits everywhere, who were quick to declare a seismic shift in our cultural landscape and the death of humor as we knew it.

At first, it looked as if they were right. Following the terrorist attacks, the late-night talk show hosts canceled their broadcasts, humor publications like the Onion temporarily stopped publishing, comedy clubs were virtually deserted, and even the notoriously free-wheeling Internet became a joke-free zone. America was in no mood to laugh and we wondered if we ever would be.

After a brief pause for grief and reflection, however, comedy slowly began to make a comeback. By the time we had mobilized for war in Afghanistan, America's humorists had begun to unleash their own salvo of jokes, satirical barbs and Web-based parodies aimed at lifting the country's spirits and cutting our new enemies down to size.

As the nation began the healing process, humor provided a much-needed salve, if not a way to momentarily escape the grim news of the day. Even New York Mayor Rudy Giuliani urged us to lighten up. "I'm here to give you permission to laugh," he said at the opening of a charity benefit in October. "If you don't, I'll have you arrested."

In the year since, our need for comic relief has not diminished -- if anything, demand for it has grown.

Far from being marginalized as frivolous and irrelevant, comedy continues to help us cope, and in many ways has served as a barometer for the way the mood of the country has changed. The fact that we can now poke fun at things like terror alerts, excessive homeland security measures, President Bush's blunderings and the hypocrisies of U.S. foreign policy underscores exactly how far we have come. It may not signal a return to political mockery as usual, but the sense of self-examination that has crept back into humor may be one sign of a return to normalcy.

The road back began hesitantly, almost apologetically, with David Letterman's return to the airwaves a week after the attacks. Forgoing his usual comic monologue, Letterman instead offered an emotional tribute to New York, setting a tone the rest of the late-night comics followed as they sought to strike the right balance between expressions of grief and the need for levity. "They said to get back to work," said "Daily Show" host Jon Stewart. "There were no jobs available for a man in the fetal position under his desk crying, which I would have gladly taken. So I came back here."

The jokes were tentative at first, steering clear of the tragedy itself. President Bush was off-limits (as Jay Leno wryly observed, "We can't do Bush jokes anymore; he's smart now.") Instead, the most successful humor targeted America's response to the tragedy and the absurdities of the emerging war on terrorism.

One of the boldest stabs at humor came from the Onion, a satirical weekly newspaper based in New York. Known for its biting social satire and dead-on news spoofs, the Onion took direct aim at the fallout from the attacks with a special report featuring such headlines as "America Vows to Defeat Whoever We're at War With," "Hijackers Surprised to Find Themselves in Hell," and "God Angrily Clarifies 'Don't Kill' Rule."

Hailed as one of the best comic achievements of the post-Sept. 11 period, the Onion provided cathartic laughs by tapping into raw emotion and subtle ironies. "We really were just trying to capture the sadness and anger everyone was feeling, and somehow it came out as humor," said Robert Siegel, the Onion's editor in chief.

"The Daily Show," Comedy Central's popular news-parody program, hit its stride when it began poking fun at media coverage of "America's new war." Dubbing its own coverage "America Freaks Out" and "Operation Enduring Coverage," the show aptly captured the way the media was preying on the nation's jittery mood, while lampooning its slick marketing of the war on terrorism.

During the anthrax scare, for example, the "Daily Show" introduced its own CNN-style news ticker, which scrolled through such breaking news items as "White Powder Found on Donut in St. Louis," "91 Percent of Americans 'Want Mommy,' " and "Oh God Oh God Oh . . ."

"Since we couldn't make fun of the events themselves, we could make fun of some of the coverage of the events," said "Daily Show" correspondent Mo Rocca. At first, that was challenging because "the mainstream news coverage of the events was remarkably restrained and responsible. But when Ashleigh Banfield started dyeing her hair and Geraldo apparently started throwing himself into the cross fire, things started moving for us again."

The biggest comedic punching bag, of course, turned out to be Osama bin Laden, continuing a long-standing tradition of demonizing and mocking our enemies during wartime. In the same way that Saddam Hussein was parodied during the Gulf War and Hitler was ridiculed during World War II, bin Laden became the new national laughingstock.

Nowhere was that more apparent than on the Internet, where bin Laden bashing became wild sport. Web humorists devised what seemed like a million comic ways to capture and blow up the terrorist mastermind in a series of games and cartoon animations that succeeded brilliantly where the U.S. military was failing. Other parodies drew upon references from American popular culture, mocking bin Laden and the Taliban in joke ads for Jihad Joe and Taliban Barbie dolls, as well as in rewrites of classic songs titled "50 Ways to Kill bin Laden" and "Osama Got Run Over by a Reindeer."

But for all the popularity of these jokes, humor researcher Paul Lewis believes it is also important to note what we were not laughing at in the aftermath of Sept. 11. He was struck by the almost total absence of the kind of tasteless jokes that have accompanied other tragedies, like the Challenger disaster. "There were not that many degrees of separation between the victims of Sept. 11 and everyone else in American culture," said Lewis, a professor of English at Boston College. "The same thing that accounts for Bush's popularity accounts for the fact that we weren't telling jokes about the 9/11 victims."

A year later, we still don't joke about the tragedy itself. But other targets that once were sacrosanct are no longer. President Bush is fair game for humor again, albeit in a slightly different way. "The Bush jokes before were Bush as the bumbler, Bush as inarticulate, Bush as a fool. Now it's a new Bush joke, because this is still an extraordinarily popular president," Rocca of the "Daily Show" said. "Now he's Bush as the sometimes bumbler who's in bed with big oil and with corporate corruption."

If Bush still has any comedic Teflon, it is wearing thin. Comedians now joke about everything from the president taking a month off to unwind (Letterman: "When does he wind?") to his motivations for a possible war with Iraq (Leno, during a recent heat wave, said he was "sweating like Saddam Hussein watching Bush's poll numbers drop.")

Comedians are now also finding fodder in things like John Ashcroft's Operation TIPS citizen-snoop program, Tom Ridge's color-coded alert system, and even FBI and CIA intelligence failures.

Last fall, when jingoism ruled and "America, love it or leave it" was the watchword, voicing any such skepticism of government policy would have been considered comedic suicide, if not a deportable offense. Bill Maher, former host of the now-defunct "Politically Incorrect," learned that the hard way after he was excoriated for making some ill-timed remarks last September criticizing certain past U.S. military actions as "cowardly."

But even if we are more self-critical and given to mockery these days, that does not necessarily signal a full return to normal or that the shift in mood has been universal. To be sure, there are still many for whom the wounds of Sept. 11 remain too raw for humor to serve as any sort of meaningful balm. And now, amid the wave of corporate scandals that have undermined faith in American business, the looming threat of more terrorist attacks, and the possibility of war with Iraq, some of us still find precious little to laugh about in the day's news.

But part of America's indomitable spirit has always been our ability to laugh during difficult times. It is an act of defiance that remains not only a fundamental part of how we cope, but who we are.

"Many things about America changed, but you can't kill humor, any more than you can kill a human emotion," Siegel of the Onion said. "You can't kill sadness or fear or joy. Obviously people are going to laugh and people will still be sarcastic and snide and ironic and winking and insincere. That's a good thing. That's a sign of the return to normalcy."

Daniel Kurtzman is a San Francisco writer and former Washington political correspondent. He runs About.com's political humor Web site (politicalhumor.about.com).