War, like Janus, has two faces: the war we see and the war within us caused by what we see. Ten years this month into the war on terror, we are winning the former, but at the cost of the latter–winning, in other words, the physical battle but losing the fight for our hearts and minds. The good news: it is not too late to turn the tides of war. The bad news: it will be soon. Let me explain.

Osama bin Laden, the grand architect of the Sept. 11 attacks, is dead, and justly so. His henchmen are scattered and in disarray. We have not suffered a terrorist attack of large scale since Al Qaeda’s deadly strike 10 years ago. Are we safer, stronger and more powerful than we were on Sept. 10, 2001? Perhaps. But we are also–undeniably and disturbingly–a bit less American. We have become less like ourselves–open, tolerant and fearless–and more like our enemies–narrow-minded, parochial and afraid. In seeking to kill us, the terrorists have failed. In seeking to change us for the worse, they are slowly succeeding.

The proof of our enemies’ quiet victory is all around us, and nowhere is that creeping victory more obvious than in the words of those who most loudly proclaim their opposition to it.

When we become who they want us to become–to use a hackneyed phrase I hereby promise never to use again–the terrorists win. The terrorists win when major Republican politicians launch a campaign to derail the construction of a Muslim community center in New York, because the terrorists have proven that we are who they say we are: a nation at war with Islam, not terror. The terrorists win when state governments amend their constitutions to explicitly ban sharia law, because they have proven that we have no faith in the strength of our judiciary. The terrorists win when Terry Jones burns a Koran, because they have succeeded in turning people of different faiths against one another in anger in a country that has always prided itself on religious freedom and acceptance. The terrorists win when American pundits and politicians call Islam a religion of hate, because that is precisely what they want Islam to become. The terrorists win every time you look askance at the guy wearing a turban on your airplane, because they have caused us to fear, rather than trust, one another. And the terrorists win every time the nation they are attacking becomes a little less worth defending–every time its values are corrupted, its guiding lights darkened, its character marred in the name of fighting terror.

Force, by necessity, must occasionally be fought with force, and this America is doing with all its considerable might. But intolerance cannot be fought with intolerance; hate cannot be fought with hate; religious bigotry cannot be fought with religious bigotry. This we have done too often and to our lasting detriment.

We can only win the ongoing war for our nation’s soul by remaining who we once were: an open society, a free society, a tolerant society. And most of all, we must remain an optimistic society–confident in the values that have animated our past and secure in a pluralist vision of a bright American future.

A story: Late in Khaled Hosseini’s beautifully compelling debut novel “The Kite Runner,” narrator and protagonist Amir returns from an immigrant’s life in California to visit a childhood friend in his native Afghanistan. Rahim Khan has become terminally ill, but a desperate Amir refuses to hear death’s knock at the door, suggesting experimental treatments, new drugs–anything to save his old friend, companion and mentor. “I see,” murmurs a dying Rahim Khan, “that America has infused you with the optimism that has made her so great. That’s very good.”

Strange, isn’t it, that it should take a minor fictional character, created by an author born and raised in a country we’ve since bombed to pieces, to remember what we all seem to have forgotten: that America’s greatest strength lies in her optimism. But 10 years this month into the war on terror, we are slowly forgetting that–and our deadly forgetfulness is gradually destroying us from the inside, as silently and inexorably as the cancer that eventually consumed Rahim Khan.

So don’t forget our past selves–they were better. And–to say something else I promise never to say again–keep America American. It’s worth it.

Want to tell Miles that you’re proud to be an American? Then email him at milesu1″at”stanford.edu.