There comes a time in all marathons when the temptation to give in becomes overwhelming. We are facing such a moment in our national response to 9/11. The enticing voices of ease and retreat are sounding louder and more confident, and our will to persist is suffering the death of a thousand cuts. Yet if we fail to persist in our response to the terror attacks we will fail, period. Mentally, we have almost fallen back to 9/10 - out of breath, unsure of ourselves, and a big, fat target for those who want to kill us.

9/11 is the first great challenge to America that we have failed to respond to as a nation. Pearl Harbor is a close comparison: more than 2,000 dead, a surprise attack by an enemy inspired to suicidal martyrdom in war. The World War Two generation would not recognize our flabby and self-indulgent reaction today. They would have won in Iraq and Iran by this time, increased the size of the military to be adequate to all challenges, and reasserted the values of liberty around the world. The Middle East has seen democratic government only in small fits and starts; but European democracy was not exactly healthy when we intervened in World War Two. We can make democracy happen in the Middle East if we use our power. The defeatist media are hoping that the 9/11 phenomenon will just go away; but it's a fool's hope.

We can blame the appeasers, the Left's constant picking at our sense of self-confidence, our downsized Clintonized armed forces. There will be a thousand excuses. But if we fail to save a whole and prosperous Iraq for the future, when we could do so with a moderate increment in military strength, the grim echoes of our defeat with resound throughout the world.

Vladimir Putin is reasserting Russian imperialism with a vengeance, the Islamofascists want to cut our throats, and the Chinese are staging open provocations against the US Navy in the Pacific. Even Venezuela's chief clown Hugo Chavez shows us his naked backside. These are only signs, but they have meaning: They proclaim that the American moment in history is on a knife's edge. The alternatives to American assertiveness in the world are not fun to contemplate. Any other power arrangement would be far, far worse than the United States.

Al Qaeda and Ahmadinejad could not destroy US armed forces in Iraq, so they did the next best thing: They stirred up civil war between Shi'a and Sunni Muslims. That strategy seems to be working, to the benefit of the mullahs and Bin Laden, our own sworn enemies. We have to understand the extraordinary forbearance shown by Shi'a leaders like Ayatollah Sistani during this period. Sistani kept on telling his following to control the temptation to take revenge, until the Sunni terror groups exploded one too many car bombs at Shi'a mosques. Iran undoubtedly meddled in Iraq, by arming and stoking the fires of Shi'a militias, until the voices of sanity were drowned out.

What Iraq needs now is an assertion of strength and will by the United States. Any other "solution" would strengthen those who hate us as the Great Satan, or those who killed 3,000 Americans on 9/11. We can impose peace in Baghdad. We can protect the borders.

It can be done. SecDef Rumsfeld and General Abizaid may have had a case for a "light US footprint" at the beginning of the war. Today things have changed. Iraqis who hope to save their country now are looking for more American troops, not fewer. Every serious war is a marathon race. Victory goes to those who can tolerate the wall of pain and still keep running. Our deadly enemies are strong in will, but weak in power - so far. If they persist and we give up, they will become invulnerable as soon as Iran explodes its first bomb. Now is the time to pour on American strength. We can win in the Middle East, or allow the civilized world to be put in far, far greater danger. This is a watershed moment in history.

James Lewis is a frequent contributor to American Thinker.