Pittsburgh’s Rashard Mendenhall has come under fire for tweets he made about the Sept. 11 attacks after Osama bin Laden’s death. (TIM SHARP/REUTERS)

Nothing matters less to me than the views of Pittsburgh Steelers running back Rashard Mendenhall.

No time should be wasted contemplating most of Mendenhall’s ill-advised comments Monday on Twitter questioning Osama bin Laden’s guilt in the Sept. 11, 2001, terrorist attacks on the United States, whether two of the four jets hijacked that day actually brought down the World Trade Center and the U.S. government’s portrayal of the self-avowed terrorist. As for Mendenhall taking exception with people celebrating bin Laden’s death Sunday, I won’t lose any sleep over that, either.

 The ignorance Mendenhall and other professional athletes have exhibited about the impact of social media, however, is concerning. Their repeated poor judgment while tweeting, blogging and posting information on Facebook has often resulted in controversy, damaged reputations and public relations problems for ballclubs. Mendenhall proved his cluelessness about the powerful tool, and it’s time for athletes to finally realize that tweeting ain’t no joke.

Predictably, Pittsburgh team President Art Rooney II, in a statement Tuesday, expressed bewilderment about Mendenhall’s tweets. And following the playbook for high-profile missteps in social media, Mendenhall apologized Wednesday in a blog post attributed to him and titled simply, “Clarification.”

Trying to explain anything confined to 140 characters is not easy, and Mendenhall would have been better served using a different vehicle to address his strong feelings about such serious subject matter.

Avoiding the topics altogether on social media would have been his best move.

Mendenhall is only 23. He has rushed for almost 2,400 yards with 20 touchdowns the past two seasons while helping the Steelers reach two Super Bowls in the past three seasons and win their record sixth championship.

The former first-round draft pick is not typically the type of player teams dump after one major non-criminal blunder. Now, though, it’s time for Mendenhall to respond to the wake-up call.

The situation should make it clear to him he’s not just rapping with his boys in the barbershop when he tweets. He’s not at Sunday dinner after church discussing things with the fam. When he uses social media, Mendenhall is speaking to the world.

Washington Redskins outside linebacker Lorenzo Alexander is among the athletes who “get it” about social media.

Alexander, Washington’s special-teams captain last season, proceeds carefully when he tweets “because you have to think about how many people are going to see it . . . and how it may come across. There’s no emotion to it, so people can interpret it however they want.”

Obviously, Mendenhall is entitled to his opinions. He has the right to express them and attempt to engage others in meaningful conversation.

A free society is strengthened by the exchange of ideas and spirited debate, and social media, especially Twitter, is all about the immediate dissemination of unfiltered thought.

A direct conduit to fans, Twitter also enables athletes to reveal as much about their makeup as they’re willing to provide.

But those are the biggest problems with Twitter, too.

Although great in theory, the actual ability for athletes to reach a large audience unfiltered, sharing potentially controversial personal beliefs, has, at times, proven to be as disastrous as one would imagine.

Everyone could benefit from having a capable editor, and outside oversight definitely isn’t part of the tweeting process.

When Mendenhall decided he should contribute to the bin Laden chatter, self-editing was his only safety net. He pushed the button — then came the uproar.

In January, another Twitter-fueled mess occurred after several NFL players and analysts eviscerated injured quarterback Jay Cutler for removing himself during the Chicago-Green Bay NFC championship game.

The Bears’ starter was labeled as a quitter in tweets, but some players backtracked after learning Cutler suffered a second-degree medial collateral ligament tear.

Athletes in this market have encountered trouble on Twitter for criticizing fans’ behavior, challenging people to fight and posting inappropriate pictures.

Of course, athletes are not alone in making unfortunate choices during the use of social media.

People in many walks of life make bad decisions every day on Twitter. But they lack the platform to draw as much attention to their mistakes.

“I deal with this with my daughter all the time,” Alexander said. “She’s quick to put a picture up or quick to write something crazy to her friends, and just not realizing that everybody out there can see this. Once you put it out there, it’s out there. And even if you do erase it, there’s really no erasing it, because professionals can still go in there and find it.

“With a lot of guys, a lot of athletes, they don’t really realize how big it is and how fast it moves. You would think they would know, but a lot of these guys just go through trial and error. As many times as you want to, you can tell somebody, ‘Don’t do this,’ but until they get hit over the head with it, they really don’t learn their lesson.”

Mendenhall is the latest athlete to figure it out the hard way.