The legacy of 9/11 can’t be fully measured even now, but perhaps the most damaging aspect can be found in our national discourse.

Taking the long view, it is possible to see the roots of today’s political dysfunction — the hate, fear, anger and resentment — firmly planted in the soil at ground zero.

Did Osama bin Laden envision such a thing when he plotted the attacks? Probably not. He might have imagined that we would retaliate, and this would cost us lives and treasure. But he couldn’t have known that we eventually would lose our common sense of who we are. This has been the big surprise of 9/11 — an ongoing, self-perpetuating act of American self-destruction.

Something was unleashed 10 years ago that bears our scrutiny. It wasn’t only evil, though the attacks were certainly that. The event was so cataclysmic and horrifying that it caused a sort of emotional breakdown in the American constitution. Simply put, it damaged our collective soul and seems to have released a free-ranging hysteria that has contaminated our interactions ever since.

No matter how many prayers uttered; no matter how many hands held or pledges made; no matter how many bombs dropped or coffins draped. A nation cannot heal itself without self-awareness. On this score we have fallen short. We seem not to want to recognize that we don’t have a problem; we are the problem.

Putting it bluntly, 9/11 caused us to go temporarily insane. Being for or against the war, first in Afghanistan and later in Iraq, divided us as wars do, but this time was different. Friendships ended, marriages suffered, people crossed the street to avoid those with whom they disagreed. Ten years later, we are still at war. Tack on the global financial crisis, stagnant unemployment, the further dissolution of trust in our institutions and we have all the ingredients for moral panic.

And now, alas, another election season is upon us with all the froth and spittle we love to loathe. President Obama understands the nation has a psychological problem, but no president in his own right mind can afford to speak publicly of such things. If Jimmy Carter was brought down by his “crisis of confidence,” aka “malaise,” speech, imagine if Obama, who already suffers an image of elitist condescension, mentioned that the nation could use a little time on the couch.

Obama tried to unite the nation with his purple rhetoric, but he missed his window when it came time to act. The jobs speech he gave Thursday night was two and a half years late and the health care reform bill he pushed through against a tide of opposition was a calamity of bad timing.

These missteps, nonetheless, don’t justify the “You lie!” hysteria of his opposition. Emotional excess and a lack of self-control in the public sphere are but two of the manifestations of our unraveling. Even as Americans listened to the jobs speech, we were reminded of the source of this ambient dysfunction as tweets flashed across computer screens about a new, credible terrorist threat.

Though we all pray this latest alarm is just the result of nasty chatter, the news may have been ironically providential. It reminds us that we are one people with a common enemy and that the cure for hysteria is purpose. Obama tried to outline one purpose with his jobs speech and a command to the Congress — a la Reagan to Gorbachev — to “Pass This Bill!” But he likely failed to reach much beyond the choir.

Instead of commanding, Obama seemed bossy. This is partly because Obama was trying to be something he’s not. He is not a pot-banging politician, but reflective and cautious. Rather than quell the emotional disarray born of fear and resentment, he pounded the drum of class warfare. He shouldn’t expect to see white flags in response.

As we reflect on the events 10 years ago, it would be nice if all sides could resolve to invite America’s better angels back to the huddle. Another terrorist attack would put things in perspective, all right, but our survival ultimately depends on our willingness to marshal reason and restraint against the emotional terrorism that surely will bring us down.

At the risk of sounding bossy: America, heal thyself. Please.

Kathleen Parker is a columnist for The Washington Post. She can be contacted at:

kathleenparker@washpost.com