There have been missteps. At this point, maybe, they’re irreversible.,Against a backdrop of scorched desert, five years of war have come and gone. Five years and still-for the freedom of others-our sailors, soldiers and air men suffer and assail the enemy.

There have been missteps. At this point, maybe, they’re irreversible. Even with the historic performance of Gen. David Petraeus, America’s vision of liberal democracy in Iraq might be unreachable.

It’s easy to gaze back and spot the flaws. It’s easy to wag a finger and shake your head-easy but pointless. The die is cast.

Putting regrets aside, tossing away the Monday morning play book, what’s worth considering now-for the sake of future operations-is how the Iraq mission disintegrated so completely. What were the stumbling blocks, both at home and abroad, and how can these be neutralized when it’s time to fight again?

From the present vantage point, two mistakes stand out sorely: We didn’t go large enough, and we didn’t go hard enough.

Shock and awe-the series of bombardments and rapid advances that opened the war-worked fine at first, but later there was too little emphasis on overwhelming force. There was no attempt at a nationwide “heavy footprint” that would be necessary to fatally stomp the resistance.

When the blitz ended and dust settled, insurgents saw that the occupation was a shoe-string affair: our lines were thin, our reserves shallow. Across Iraq, they proceeded to write a response to the invasion in the blood of our troops and their fellow citizens. Lacking sufficient American support, the government developed a weak constitution. We are still paying for that initial fumble.

The moral: never again can we enter a significant conflict without an enormous dedication of manpower and resources.

Such dedication will require, almost certainly, a military draft, a conscription that draws upon all classes and age groups. That sweeping measure will ensure sufficient troop levels, and the involvement of the whole nation.

After all, could we have bested the German and Japanese empires without the entire republic’s weight? It took some sixteen million citizen-soldiers to extirpate authoritarianism in those places.

It’s also necessary to revert to an earlier understanding of the parameters of conflict in general. Americans must quit the fantastic notion that we can meet our enemies with gloves on, so to speak.

Look at our track record after the second world war: In Korea, a narrow, unsatisfactory victory; in Vietnam, a miserable flop; in Iraq, a disheartening stalemate. The problem, especially in the latter two situations, is that we fought with one arm tied behind our back. We can no longer fight with hands clad in bubble wrap.

That means no press men snooping around American war prisons, no D.C. micromanaging, no restraint in the handling of enemy enclaves, no hesitancy about using weapons shunned by the collection of American protectorates that constitutes the respectable “international community.”

Halfway measures-like striking a bargain with the religious militias, which are beginning to stir once more-allow for protracted bloodletting, which multiplies misery. Had we been more thorough and far-reaching, less sentimental and restrained in the campaign against extremists in Iraq, chances are we wouldn’t be trapped there today.

What we didn’t learn after Vietnam we must learn from this Mesopotamian dust-up: marshal the entire populace behind a war and fight with Roman ferocity from start to finish.

We are living, to lift a line from Robert Lowell, in an age of piety and iron, although some have yet to absorb this bitter truth. Undoubtedly, our country will be provoked to war again, whether by a tin pot tyrant in South America or by the crude menace of radical Islam. When next the battle flag flies, let’s get the job done right.