Historians usually are able to look back and pinpoint the factors that caused the greatest of nations to fall into decline. If it ever comes time to dissect what happened to the United States, they likely will boil it down to one word: winning.

Yes, folks, when a Charlie Sheen manic outburst becomes an inspirational motto for a nation, it's the beginning of the end.

Sadly, historians likely will have other moments to illustrate the cultural collapse, including Kim Kardashian's blink-and-you-missed-it marriage, which generated more money than some cities' annual budgets, and the fact that some people took Donald Trump's possible presidential candidacy so seriously.

No wonder the Occupy Wall Street protest avoided the 1 percent's crazy sibling, Hollywood.

Keeping it 'klassy'

Some things are meant to last one season: bright pink flip-flops, a relationship with George Clooney, the McRib at McDonald's. But not marriage.

And while celebrity marriages can flame out quickly, the implosion of Kim Kardashian's 72-day union with Kris Humphries was all the more spectacular because of the hype that preceded it: the 20.5-carat diamond engagement ring, the engagement party, the three wedding-day gowns, the two-part TV special.

Even Kate Middleton would have said, "Enough already!" It was more distasteful because it was filmed for her reality show, garnering her more cash than gifts.

By the end of the year, the backlash was so strong, she headed to Haiti for charity work, looking to improve her bruised image. Or, perhaps, for hubby No. 3.

If this is winning ...

Celebrities have meltdowns in public all the time, yet we hadn't had a really epic breakdown since Britney Spears shaved her head.

Maybe that's what made Sheen's collapse so transfixing. He gave us everything we expected in a train wreck, and more: Custody battles! Jittery interviews! Goddesses! And of course, "Winning!"

Watching his daily dose of acting crazy was more entertaining and addictive than any episode of "Two and a Half Men."

But we overdosed when Sheen went on his stand-up tour, which basically gave him a pass to go on rambling diatribes on foolish people's dimes.

Baby daddy?

We didn't realize Justin Bieber had reached puberty, so it came as a shock when Mariah Yeater claimed he was the baby daddy to her months-old son following an alleged romp after one of his concerts, when she was 19 and he was just 16.

A paternity suit was filed, DNA tests were bandied about, all while Maury Povich salivated from the sidelines. But, alas, we never got a chance to see Bieber do the customary pimp-walk strut to the phrase, "You are NOT the father!"

Yeater withdrew her paternity claim as her story started to collapse and Bieber took a paternity test. We would have preferred that Biebs prove his manhood with a passable mustache.

Emperor Donald

Donald Trump got the media buzzing when he announced his intention to run for president -- maybe.

To burnish his credentials as a conservative Republican, he seized on the so-called "birther" bandwagon by stoking doubt about President Barack Obama's U.S. citizenship.

In the end, Obama released his Hawaiian "long form" birth certificate proving he is indeed a "natural-born citizen," as the Constitution requires. And, unfortunately, so is Trump.

Private jets

Proof that celebrities should fly only on private jets: they cannot behave themselves on commercial flights.

Alec Baldwin was kicked off a flight for refusing to stop playing a cellphone game while the plane was parked at the gate.

Green Day's Billie Joe Armstrong was denied a seat because of his sagging pants.

And Gerard Depardieu urinated on a plane ahead of takeoff, apparently unable and/or unwilling to hold his bladder until he got the OK to move about the cabin.

Next time you see a celebrity on your plane, instead of asking for an autograph, ask for a seat far, far away.

Duck!

Chris Brown's star, seemingly forever tarnished after beating then-girlfriend Rihanna, was on the rise when he decided to go on "Good Morning America" to perform and talk to host Robin Roberts.

But Roberts' decision to ask about the Rihanna incident got under Brown's skin. After the interview, he trashed his dressing room, even breaking a window. Yet people continued to buy copies of his comeback album.

Twins?

When Maria Shriver announced that she was divorcing Arnold Schwarzenegger after 25 years of marriage and a stint in the California governor's mansion, we thought it was because she'd finally seen those tiny Speedo pictures.

But then we learned that not only did he cheat on her with the family housekeeper, but he and the housekeeper had a son together around the time Maria gave birth to their child, also a boy.