During a week-long sojourn to Florida over winter break, I encountered a man named Top. Top was a shuttle bus driver, but, more importantly, Top was a chatty shuttle bus driver.

While most drivers are content to announce stops and — if you’re in Orlando, as I was — provide Disney trivia, Top decided that his job was to invigorate a crowd of unresponsive, heat-stroked passengers by occupying every single second of the trip with his voice.

Top was my bus driver twice, and I soon learned that his repertoire was carefully calibrated to last through the duration of a one-way trip; relying on the quick turnover of a tourist crowd, he would repeat the same shtick each day. First he would introduce himself to the passengers, mentioning both his previous service in Vietnam and his current occupation as a substitute gym teacher. Then he would ask if anyone on the bus was from another country, and nobody would respond. “Another country” would be modified to “another state” and, still, no response. That’s when Top would break out the jokes.

“What do you call two Mexican guys playing basketball? Juan on Juan.” (Several people chuckle.)

“Here’s one for the kids. Why was Tigger looking in the toilet? He was looking for Pooh.” (Little kids giggle.)

“Why are there no Wal-Marts in Iraq? Because there’s a Target on every corner!” (There is dead silence as everyone shifts uncomfortably in their seats, exchanging wary glances.) “Get it? Target? Tar-jay?” (Several teenaged girls laugh because they, too, call it Tar-jay.)

The reason for the joke’s icy reception was twofold. The first, and most obvious, reason was that it just wasn’t particularly funny. But even if it had been uproariously clever, I doubt that the crowd would have been very responsive; jokes about war don’t tend to go over too well.

When does it become acceptable to laugh about a tragedy? The question is one that has been raised far too many times in the past few years, as a world beset by one disaster after another struggles to comprehend. An episode of South Park placed the figure at 22.3 years, a number that was likely chosen less empirically and more instrumentally, serving to defend an episode revolving around AIDS jokes. Not coincidentally, that episode, “Jared Has Aides,” has been banned on several syndicates; apparently 22.3 years was an underestimate.

More importantly, why is tragedy humor so patently offensive? The role of humor as a coping mechanism has long been acknowledged, proven both through medical research and self-reflection. Laughter is a panacea; it improves mood and, ultimately, physical health.

Of course, what works in theory doesn’t always work in practice, and although humor may be a natural defense mechanism when one is confronted with tragedy, it often comes off as trivializing or cruel. TShirtHell.com, an online store that sells decidedly non-work-safe apparel, was bombarded with hate mail after it released a spoof on the ubiquitous “I (Heart) NY” shirt, in which the heart was replaced with the silhouette of an airplane. In a more recent insulting spree, an “I surfed the tsunami, 2004″ shirt hit the e-stands a mere week after the Indian Ocean tsunami killed tens of thousands.

Hot 97, a radio station in the city, recently came under fire when its morning show played a song parodying “We Are the World.” The song, which was supposed to be clever — but, even from a neutral standpoint, fell unbelievably short — included lyrics such as, “So now you’re screwed, it’s the tsunami / You’d better run or kiss your ass away, go find your mommy / I just saw her float by, a tree went through her head / And now your children will be sold to child slavery.” The show’s staff was suspended indefinitely, which, judging by the fact that they tried to rhyme “head” with “child slavery,” will be no huge loss.

It isn’t just the fact that people are cashing in on tragedy that raises ire; if it were, the proliferation of “Always Remember” sweatshirts and “Never Forget” musical refrigerator magnets would be found just as repugnant by the sensitive consumer. While other defense mechanisms — such as denial or projection — are viewed as the inevitable result of acute grief, laughter seems demeaning and trivializing. To laugh at something is to treat it as a boondoggle; to derive mirth from something is to call it pleasant.

But consider what a majority of jokes are about: sex, death and excretion. These are hardly trivial matters, nor are they (always) pleasant — in fact, their import is what makes them into seminal (pardon the pun) joke-fodder in the first place. Jokes are a form of sublimation, channeling a natural impulse into a more socially acceptable activity. While it’s not exactly couth to discuss bodily functions in public, bathroom humor is a sanctioned way of bringing such topics about.

Little kids don’t experience this need to sublimate. When one small child wants to make another one laugh, all he needs to do is say a taboo word — a simple “poop!” will send a group of toddlers into hysterics for quite some time.

However, we’re not little kids, and we can’t always shout out exactly what we mean. Instead we cloak our meanings in every way possible, through art and standoffishness and, yes, jokes. The teenager in an “I (Airplane) NY” t-shirt may be hurting even more than the knee-jerk flag-waver. The person telling the “now you Sri it, now you don’t” joke may have pledged a week’s salary to the Red Cross.

The hosts of Hot 97’s morning show may be introspective, sensitive individuals who were so impacted by the tsunami that they could only express their grief in the form of a poorly-written and ill-performed song.

Just kidding.