When the nation's largest military base is turned upside down by a gunman, in effect becoming a bloody battlefield, certain truths come to light.

I humbly submit four observations about the Fort Hood tragedy, the last of which may prick a few consciences and rattle some cages.

It all needs to be said.

Let's start with the obvious: All the men and women who enlist to serve our nation make tremendous sacrifices to do so, even when their lives aren't in imminent danger.

God bless them one and all.

No. 2: Our soldiers and their command staff are subjected to extreme levels of stress that simply are unimaginable to us civilians who report to our cubicles every day with only traffic, weather and the mortgage to worry about.

No. 3: If an insulated, closely guarded military installation on American soil isn't safe, that should signal to all of us that the term "national security" is an oxymoronic ideal at best.

No need to panic, mind you – just another stunning, tragic reminder that we're all vulnerable, all hoping and praying to see the sun come up tomorrow, whether we reside in Killeen, Texas, or Kalamazoo, Mich.

And No. 4: Some Americans of Muslim faith are suffering from a fundamental crisis of identity in this country in the wake of 9/11.

If early reports prove credible, Maj. Nidal Malik Hasan, the 39-year-old Army psychiatrist accused of gunning down his fellow comrades, had grown conflicted and confused about his military responsibilities and his Muslim beliefs.

This is no excuse for his cowardly behavior, mind you. And it most assuredly isn't an attempt to rebuff armchair theories that Hasan is merely another in a long line of nut-jobs who came tragically unglued.

Maybe that's all it was.

Still, it's clear that much more needs to be explored and explained about Hasan before more folks are tempted as they always are to pick the lowest fruit and start another unfruitful round of Muslim bashing.

Don't know about you, but I'm baffled as to why Hasan's changing demeanor didn't raise red flags long before he snapped at Fort Hood.

In hindsight – which, granted, always provides the clearest view – he bore the markings of a desperate man, one stuck on a railroad track with two trains from opposite directions bearing down on him.

Relatives recalled Hasan's increasingly vocal opposition to the wars in Iraq and Afghanistan, a view that certainly is not unique or limited to Muslims. But what is pointedly different in Hasan's case is that, on top of all that, he'd been harassed and called names because of his religion.

"He would make comments to other individuals about how we should not be in the war in the first place," one fellow officer, Col. Terry Lee, told Fox News Channel. "He made those comments, and he stuck strongly to his faith."

That strikes me as a readily combustible cocktail of emotions and dueling convictions that one could reasonably conclude would set off bells and whistles with the Army's brass.

For some reason, it did not. Moreover, Hasan made repeated requests – all of which were denied – to get out of the Army before he'd fulfilled his commitment, even offering to pay the Army back for the education he received, relatives said.

So what started out as an admirable personal pledge – against his family's wishes, I might add – to serve the country where he was born gradually turned into a desperate plea for release and a profound fear of being deployed to Iraq or Afghanistan.

Along the way, Hasan, the son of Palestinian immigrants, lost his sure footing – and a clear identity.

Tragically, no one picked up on Hasan's troubled way of thinking, no matter how many red flags we all can now see.

So we're left to mourn the 13 dead, more than three dozen wounded and many, many more who are hurting.

To them, we all owe an eternal debt of gratitude.

But if there's one lasting image I wish to take away from the Fort Hood shootings, it is that of valiant military personnel "ripping their uniforms," as Lt. Gen. Robert Cone put it, "and taking care of each other."

That, in a nutshell, is the true heart and soul of an American soldier – and no mad gunman can take that away.