That the Fort Hood gunman had plenty of enablers is unmistakable. But the fact that a number of red flags were ignored by so many is perfectly understandable given the context. Here is the reality:

Despite all the exhortations to report suspicious behavior in a post-9/11 world, we have seen the creation of a perilous climate in which the fear of offending has overtaken common sense even when lives are at stake.

The sanitization of American speech and thought has been building for some time. Before al-Qaida, the sort of idiocy evident on the home front would have been good fodder for the world of talk radio, but otherwise unworthy of more than short rants. I speak of things like the cancellation of Ladies’ Night in bars after a man complains about paying more for a drink than a female patron. Or the honor guardsman prohibited from saying “God bless you” as he hands an American flag to a grieving family at a military funeral. The teachers who grade tests with purple ink instead of red to avoid harming the psyche of an underperforming student. And the Little Leagues that hand out trophies to losing teams just for showing up.

But now these incidents have greater meaning, because the thinking behind them has impeded our ability to defend America. It has become taboo to suggest that in a war initiated by young Arab males who are religious fanatics, we should give heightened attention to young Arab males who might be religious fanatics. It is counterintuitive, and now catastrophic.

According to 9/11 Commission testimony, the Department of Transportation prohibited airlines from designating more than two individuals of the same ethnicity for secondary screening per flight. As 9/11 Commissioner John Lehman told me a few years ago: “The fact is, our enemy is the violent Islamic extremism, and so the overwhelming number of people that one need to worry about are young Arab males, and to ask them a couple of extra questions seems to me to be common sense.”

The Transportation Department, however, didn’t agree. United Airlines and American Airlines — who combined lost 33 crew members and hundreds of passengers on 9/11 — were each fined $1.5 million for discrimination complaints lodged against them in the months after the attacks. Continental Airlines, meanwhile, coughed up $500,000.

Then there were the five Arab men who aroused suspicions by praying near Giants Stadium’s main air duct and food preparation area during a New York Giants-New Orleans Saints game in September 2005. That the game was a Hurricane Katrina fund-raiser attended by former President George H.W. Bush still didn’t stop the men from publicly complaining about being detained and questioned. The outcries of the offended caused stadium officials to set aside a designated prayer area, no doubt a concession meant to stave off a lawsuit.

The so-called “flying imams,” meanwhile, just settled their own lawsuit last month. Other passengers on a November 2006 flight from Minneapolis to Phoenix claimed the six Islamic spiritual leaders were praying and chanting before boarding. Some reported hearing the men bad-mouthing George W. Bush and the Iraq war while invoking al-Qaida and Osama bin Laden. Their seats were scattered throughout the plane, and several requested seat-belt extenders despite not being overweight. They, too, were questioned and released.

Their attorney classified the case as one of “flying while Muslim.” The resulting lawsuit — which named US Airways, the Minneapolis airport authority, and the investigating police officers and FBI agent — was settled for an undisclosed sum last month.

Notice the pattern? All cases of Americans doing what they’re repeatedly told to do: report suspicious behavior. All were met with public criticism or the obligatory discrimination lawsuit.

Every slight.

Every insult.

Every look askance.

Today, anything is grounds for the proverbial federal case. Indiscretions that once would’ve been settled with a hand gesture are now grounds for litigation. Worse, the muzzled, victim-filled society we have created now impedes the war on terror.

Want to know why, eight years after 9/11, we still don’t look for terrorists at airports and borders by keeping in mind what all the other terrorists have looked like? Because we’re afraid to offend. We have become a country of kvetchers and apologists, even while at war. The same thinking that says kids on losing T-ball teams should get a trophy, or that an “F” grade should be delivered in purple, not red, puts interrogators in handcuffs at Guantanamo or precludes looking for terrorists at airports who — look like terrorists!

It’s no wonder that military supervisors and intelligence agents were reluctant to act against Maj. Nidal Malik Hasan — despite the troubling PowerPoint presentation on Islam; the communications with Anwar al-Awlaki, the imam called the “spiritual adviser” to two of the 9/11 terrorists; the increasingly disturbing views of the wars in Iraq and Afghanistan, and the discussions about Hasan’s mental health at Walter Reed Army Medical Center. No doubt that list will be expanded in the coming months.

It’s not enough to attribute it all to “political correctness.” The finger-pointing in the days after the Fort Hood shooting have robbed that term of its bite.

The broader message of the last eight years is clear: Report troubling behavior at your own risk. Without an unimpeachable smoking gun, you could be smacked with a lawsuit, subjected to an investigation, or labeled a xenophobe.

Unfortunately, the lesson from Fort Hood is that by the time that smoking gun turns up, it’s often too late.