Serving in the Navy in the rivers of Vietnam, struggling against fear and rage, I had a commander who warned that we faced two enemies, not one. One external - there, the Viet Cong. One internal - the animal within, that war could unleash. Fight both enemies, he admonished, or we'd forget what we'd thought was worth fighting for. Fight both enemies, or no one could tell the players without a scorecard.
Fight both enemies, he concluded, or we'd be fighting neither - simply because he'd court-martial us and send us to the brig.
War is not only a danger to our lives; it is a danger to our humanity. So when we review words and documents to learn how things go wrong, we must not just ask what leaders said, but what they should have said but did not.
We stress force protection: Minimize casualties and bring our troops back safe. But mortal danger is half the threat of battle. We need spiritual force protection, to prepare for moral dangers, too - so that when war threatens our innocence, we do not also lose our dreams and souls - and our control.
We humans can do tremendous good or enormous evil. Native Americans teach that there are two wolves within our souls - one noble, one rabid - and which wins depends on which is fed. War can numb our sense of good and feed the beast within. The problem isn't that we don't have good people in uniform. The problem is that war can turn even the best into different people.
"There are no atheists in foxholes," goes the saying, but foxholes can breed atheists, when those who see war's nightmares lose all faith in dreams - and fight fire with fire and dog eat dog are the only values that survive.
None of the Abu Ghraib abuse reports I've seen mention chaplains, who normally serve with prison and intelligence units to help us all remember human values we share, regardless of faith. If leaders didn't make use of chaplains, that may be one more failure - of the leaders, or the chaplains. Using all the tools at their command, leaders must prepare their forces to withstand threats to judgment, ethics, and morale.
Ethics is a complex issue, and more so in war when our nation rightly sanctions deadly force in ways unacceptable in peace. But even just ends do not justify all means, and we must control our outrage before rage takes control of us. We must defend the values and beliefs that make us what we are, and who we must remain.
Our enemies seek to expose our values as false. The war on terror is, in part, a war to defend an image of the US that gives hope to those who would be free. American values are our strength, and when they come under fire - as they most surely will - we must protect them as courageously as any other strategic stronghold we defend.
We condemn terrorism because we believe some actions cannot be justified, no matter what. But do we believe that claim, ourselves - and accept some limits even when innocent lives might be at stake? We must practice what we preach. The hard truth is that even tragic deaths are sometimes preferable to monstrous acts.
When General Eisenhower visited Ordruf, a World War II concentration camp in Germany, he directed that atrocities be publicized for the sake of American soldiers. GIs don't always understand what they fight for, he said, so let them understand what they fight against. And, I would add, what they fight against becoming.
Leaders must set rules of combat and engagement, even as they lead the fight against those whose only rule is to kill and kill again.
Reasonable men and women must debate where to draw the lines. But setting limits is the beginning, not the end. Good leaders must train their forces to recognize, understand, and fight all the enemies they will face.
Unless we understand the enemy within, then - as I learned long ago - we'll remember how to fight, but not what it was that was worth the fight. Neither Americans, nor their enemies, nor those they seek to help, will know the players without a scorecard. Then, even if we win the battles, we will lose the war.
• Rabbi Arnold E. Resnicoff is a member of the Board of the Carnegie Council on Ethics and International Affairs. He served as a combat officer in Vietnam, was a military chaplain between 1976 and 2001, and was present at the 1983 suicide bomgin of the US Marine barracks in Beirut.