If you didn’t have, say, a sense of smell, and 3,000 people all informed you Casablanca Lilies were pleasantly fragrant ”” you’d rely on that information and assume they were right. Now if you didn’t have, say, a sense of humor, and 3,000 people around you all guffawed uncontrollably at jokes about you ”” best you’d rely on that information and at least smile. This would cloak your defective funny bone and lack of self-irony. You’d appear affable instead of culturally tone deaf.

Cut to: Donald Trump’s protruding lower lip as he scowled at jabs mentioning him at this year’s White House Correspondents Dinner. Trump has been relentlessly trumpeting the “birther” conspiracy as part of the charade that he’s running for president. A bid for attention and ratings is more likely. But he’s been capitalizing on the Republican rumor that President Obama wasn’t born in the United States. Trump boasted how proud he was that he “did what no one else could” and made the leader of the free world release his long-form birth certificate halfway through his first term” won via landslide.

Trump even claimed he sent a team of investigators to Hawaii to find out if the President of the United States was really born there. He’s yet to release any evidence of this alleged investigation, but Republicans are still more likely to believe that story than they are in Obama’s eligibility to serve as chief executive.

Basically, Trump was begging for some proverbial chop busting. He showed up last weekend at the swanky DC gala of journalists and celebrities, and the President was armed with some Trump/birth certificate bon mots.

“Donald Trump is here tonight!” said Obama. “I know that he’s taken some flak lately. But no one is happier, no one is prouder, to put this birth certificate matter to rest than The Donald. And that’s because he can finally get back to focusing on the issues that matter””like, did we fake the moon landing? What really happened in Roswell? And where are Biggie and Tupac?”

Between Obama and headliner Seth Meyers, Trump was the butt of most of the evening’s jokes. He laughed at none of them ”” making Trump the only one who didn’t find them hilarious.

When you don’t have a sense of yourself, it’s possible to be a joke without even realizing it. Bill Maher on his show Real Time last Friday said, “Trump’s hair, it’s a dilemma for a comedian, because, for one thing it’s one of the funniest things we’ve ever seen. On the other hand, everybody is doing hair jokes on Donald Trump.”

The more ridiculous Trump becomes, the easier the bits get – the more abundant they become. There is such a thing as bad publicity – it’s in the form of a joke. It’s tough to recover politically from being a punchline. Just ask Dan Quayle.

Minutes after the President announced Osama bin Laden was dead, filmmaker Michael Moore tweeted, “No matter what Obama says, bin Laden’s not dead until Donald Trump sees his death certificate.” Then Mo Rocca made the same joke; Then New York Times columnist Nicholas Kristof, comedian Albert Brooks and author Tom Bodett. Then hundreds if not thousands of other less notable joshers tweeted the same idea. Masses of others retweeted it. Business Insider ran a satirical piece with the premise. In a record setting Twitter event ”” this was an unprecedented amount of identical Twitter quips.

Before Twitter existed, a comedy writer once told me a “Leno joke” is defined as the first joke you think of and throw out that Leno will do that night. Comedian Andy Borowitz wrote me, “In the Twitter era of comedy, the first person who makes the joke is the winner and everyone else is a Winklevoss.”

But what is it when hundreds all have the same thought at the exact same moment? A wisecrack so widely and independently generated there’s no possible ownership for it?

What this example of parallel thinking tells me is that Trump is, in fact, a joke. The first sign you’ve become a parody of yourself is when the jokes about you write themselves.

Trump is still pretending he’s going to run for president. He, of course, has said he wants to focus on real issues like $5 gas.

I think we should appropriately demand to see the proof.