Until then, we knew only freedom. We had the luxury of whimsy. We could indulge our neuroses.

America has changed. And we have all grown immensely, in only seven days.

Our nation no longer looks down, from its lofty superpower perch, on the vulnerable. We are vulnerable. We have realized that we too are citizens of a dangerous world -- a world about which we have so confidently warned others.

In that world last week, streets and newspaper racks stood empty. All conversations were the same. Fighter jets roared overhead. Thousands lay dying, dead, their ashes scattered. Our usual business was no longer usual. Our whimsy evaporated into a new atmosphere of peril and hate.

But this nation, born of fire and defiance, of principle and hope, has not broken. The united strength of America is manifest everywhere -- in word, flag, and song. Fire and defiance again go hand in hand.

Who opposes us? America has many enemies -- those who resent our freedom, denounce our liberty, excoriate our openness. Crowds last week trumpeted our losses and celebrated our dead. The world must know, however, that anyone who cheers the death of an American is an enemy of America.

Talk of retaliation is not rooted in hatred, neither in aggression nor revenge. To endure, we must defend ourselves. We must protect our homes and families, endangered as we never knew. We must preserve freedoms so fiercely won, principles so nobly consecrated. And we shall.

We cannot defeat terrorism if we succumb to terror. We cannot defeat hatred if we succumb to hate. America must endure as we knew it, as the "great peaceful people" who cherish liberty above all else. If our path must be of safe repression or dangerous freedom, we must choose the danger, and stand against those who would challenge our resolve, in the name of all we have always upheld.

America cannot exist as a police state, a nation paralyzed by fear, haunted by death. We may be threatened, but we will not forgo our freedom. Storied struggles of America's past suddenly come alive as we realize we are taking our place in the history books, beside the Revolution, the Civil War, the World Wars. A new generation is learning what it means to be American.

Our enemies fear reprisals, as they should. Even in the twenty-first century we must struggle for existence, and we must strain, and sometimes sacrifice, to emerge victorious. Harder still, the American burden includes not just treasure and territory but values and ideals, which cannot be protected with tanks or missiles. Our hearts and minds are our only safeguards.

Adult America may forget its whimsy for a time as it considers important new questions of security, surveillance, transportation, prejudice. Answers must be thoughtful, not rushed; passionate, not convenient. Our own fears must be quietly dispelled.

We must stand with our neighbors, our fellow citizens, our allies. Prejudice against our enemies may pull on our hearts but cannot be allowed to infect our minds. Our enemies are solely those who wish us evil and would have us dead; dress, race, religion are indicators as reliable as favorite color, height, toothpaste preference.

As never before, America speaks with one voice, with which we reassure our own as we plan for the future. To the friend who whispers, in haunted tones, "I don't want to design bombs," we must say, "And you won't." To those who worry that life will never be the same, we must answer as best we can, with the truth.

Life may never be the same. But of this we can be sure -- America will never be a nation of terror and of hate. Whoever our enemies, whatever the challenges, as have we always done, America shall prevail.