The enemy within.

Byline: The Register-Guard

What if it were possible to hear the sound of millions of hearts breaking at the same time? What kind of sound might that make?

Something similar to the sound of shattering glass and sirens, screaming and sobbing, all mixed with something softer, like an incongruous blizzard of paper fluttering to the streets of Manhattan in a dust-choked wind.

Or maybe something deafening, like an explosion inside a schoolhouse, mixed with something softer, like the whimpering of wounded children and the speechless horror of rescuers who realize they have arrived too late for too many.

What if it were possible to hear the sound of millions of hearts hardening? What kind of sound might that make?

Something similar to the sound of helicopter gunships and howitzers, mixed with something softer, like the sound of shovels scraping shallow holes in barren ground.

Or maybe something bestial, like the snarling of a German shepherd inches from the face of a terrified prisoner, mixed with something ordinary, like the buzzing of flies.

The sounds of Sept. 11, 2001, and Sept. 3, 2004, rise above a terrible chorus of innocent suffering elsewhere, heralding a fearsomely changed world. Equally fearsome, by design, are the sounds generated by the responses to the heinous acts of terrorism that have forever changed the definition of war.

Three years after 3,000 Americans perished at the hands of militant Islamist terrorists, Chechen murderers half a world away confirmed our worst fears: This new war has no rules whatsoever, no boundaries of decency or basic humanity, no moral taboos. President Bush was right; these suicidal fanatics are most certainly evildoers.

But the moral dilemma Americans face on the third anniversary of the Sept. 11 attacks remains: If the enemy will stop at nothing, does that require or justify an equally ruthless response?

The answer must continue to be an unequivocal "no." Unless Americans maintain the moral authority to insist that some actions cannot be justified, even in self defense, we will have become the enemy. When the faces of two fighters are covered in blood, it is impossible to tell them apart.

Much blood has already been shed, and there is no end in sight. One thousand U.S. soldiers and more than 10,000 Iraqi civilians have died to date in the Iraq war. Already, Americans have acquiesced to "wanted dead or alive" policies that are tantamount to assassination, grown numb to civilian casualties and largely minimized evidence of widespread prisoner abuse in Afghanistan and Iraq by U.S. troops.

More ominous still are the once-unthinkable scenarios that contemplate the use of tactical nuclear weapons.

The terrible engine of war needs no conscience to operate efficiently. It's fueled by bullets and bodies, and victory typically goes to the people who have been able to inflict the greater harm. Combat veterans consistently report that in the heat of battle, the only rules followed are the ones that enhance survival.

Three years after Osama bin Laden's henchmen forced Americans to recognize that they faced a new and fiercely determined foe, it's important to remember that in this very different war, there are two enemies: the one without, and the one within.

The enemy without knows it cannot win a conventional war against a military superpower, and so it seeks with escalating acts of horror to provoke the enemy within.

The enemy within feeds on outrage and a desire for vengeance, attempting to overcome our humanity with rationalizations like "at least we don't behead our prisoners or target women and children."

President Bush was absolutely right when he declared that the United States cannot win the war on terror, in a conventional sense, but that it can, with the help of other nations, make it increasingly difficult for terrorists to succeed.

Even a qualified victory won't be possible, however, unless the U.S. and its allies have successfully resisted the terrorists' provocation to respond to cruelty with brutality, to injustice with oppression and to fanaticism with institutional intoler- ance.