Can you take a joke? Can you take a joke about something not so funny?

Shortly after 9/11, an Internet joke circulated that Americans were reluctant to volunteer to fight Al-Qaeda out of patriotism until they learned that “Al-Qaeda killed Dale Earnhardt — a famous Nascar racing star who’d died earlier in 2001 in a fiery car crash during the third lap of the Daytona 500.

A rude photograph showed a band of obese, unkempt, previously inert southern good old boys suddenly grab their rifles, pull up their saggy jeans above...well, shall we say, their tummies, raise the Stars and Stripes, and head to Afghanistan.

And if America’s men would grab their guns to fight Al-Qaeda for Dale Earnhardt, imagine what they’d do if they believed that Al-Qaeda killed NFL “safety” football star Pat Tillman, who turned down a $3.6 million contract with the Arizona Cardinals to enlist in the US Army to fight “the global war on terror.”

Behind every joke there’s a true thing. Behind this joke lies the power of the hero.

Even in death, heroes inspire. A hero’s death encourages imitation and embracing the values that led to hero to his fate — especially if the hero’s mission is left uncompleted by his demise.

Lesser folks are spurred to action by the hero’s sacrifice — and “sacrifice” is a word US President George W. Bush uses in almost every speech he makes.

The hero’s death inspires people to finish the hero’s fight. And then, there’s vengeance....

So one understands why the Pentagon and the Bush administration might have, in the words of the normally staid New York Times’ story on Army Specialist Tillman of the Second Ranger Battalion this week, “conspir(ed) to exploit a famous soldier’s death” by claiming Tillman was killed by “devastating enemy fire.”

But did they conspire to do anything more?

The Times, which does not mince words, called the Pentagon’s “incompetence” in investigating Tillman’s death “astonishing.”

And “astonishing” means more than mere surprise. It implies incredulity — that someone or something is beyond reasonable belief.

The Times demands the Pentagon explain why it “concocted a phony story.”

A few high-ranking but retired generals will pay the price of a star or two for the Tillman scandal, but the Pentagon has not yet released the full panoply of their records and reports.

That is odd — not to quibble, but when Earnhardt died in a car crash that did not at first appear serious, Nascar made nearly every detail of his death public. And the founder of the company that manufactured Earnhardt’s seat belt resigned.

The Pentagon has, however, made an interesting change in how they describe why Tillman was killed. “Fratricide” — the crime in which somebody kills his or her own brother — is how the US military now says Tillman died.

They stopped saying “friendly fire” after Tillman’s family insisted the three fatal bullets in Tillman’s forehead proved his death was anything but “friendly.” The one word the army is not yet saying publicly is “frag” — a slang term from “fragmentation” that slipped into America’s lexicon during the Vietnam War to describe how American soldiers in battalions like Tillman’s murdered fellow soldiers and commanding officers with fragmentation grenades, which left no fingerprints, and resulted in no incriminating ballistics reports of matching bullets to guns and measuring feet of impact from killer to target.

Did Tillman’s fellow soldiers accidentally kill him? Did Tillman’s killer or killers miss “the enemy” and accidentally hit “the friendly?”

Or did they fire at him deliberately? And if they did fire deliberately, did they do so because they had incorrectly identified their target, Tillman, as “the enemy?” Or did Tillman’s fellow soldiers intentionally murder Tillman with premeditation? Did one or more American soldiers “frag” Tillman?

The idea that Tillman’s band of brothers would have a murderer or two among them incites fury not only across the Internet, but at all levels of American discourse.

But since the Pentagon and the White House claim to usually act competently and with great purpose but nevertheless, in the words of the New York Times, “concocted a phony story” about Tillman’s death, one has to ask: Does the enormous cover-up and embellishment of Tillman’s death hide anything more sinister than embarrassment?

We want to believe the best about our bands of brothers.

But a draftless, “all volunteer military” is one where Americans self-select for a line of work that involves behavior that would be sadistic were it not that the formal niceties of war create limited justifications for it.

One need only look again at Abu Ghraib’s haunting photographs — images taken not to document sadism, but because the sadists involved were proud of what they did there — to demand the full truth about how and why Tillman died.

It’s no joke.