WASHINGTON -- On the morning of Sept. 11, 2001, with President Bush visiting Florida, I was working from home in Alexandria, Va., on some forgotten domestic speech the president never gave. As events unfolded in Manhattan, I left for the White House. Nearing the Pentagon, I saw a plane flying low over the highway -- so low I could clearly see the windows. It was only later that I considered the fear behind them.
What followed, for my part, was years of words. Words of comfort. Words of resolution. Words in cathedrals and before Congress and at military cemeteries.
But now, finally, the words of Osama bin Laden's obituary.
9/11 was the cruel and random suffering of an earthquake -- but an earthquake with an author, well pleased by his work. Nothing was more obscene that day than his delight.
On 9/11, however, America awakened to problems larger than one man's evil and goals greater than his punishment. The main strategic consequence of 9/11 was to lower America's threshold of acceptable risk. In a world of countless dangers, a president must choose which to confront and which to tolerate. A threat that germinated in Sudan and thrived in Afghan training camps had been considered worth monitoring but not ending.
Following 9/11, this and similar threats would not be tolerated. Call this pre-emption or hide behind euphemism, but an American president could no longer allow dangers to fully form before acting. The Afghan War became inevitable. The Iraq War was wrong in diagnosis but not in theory -- far fewer would have objected if weapons of mass destruction had been found. The prospect of a nuclear Iran became less acceptable. Drone strikes and special operations raids against terrorist targets began and still expand.
The result has been a global war of varied intensity and uncertain duration. By the measure of preventing terrorist attacks on America, it has been a success. By the measure of military casualties, it is a sad and continual burden. The rules of this unprecedented conflict have been improvised by generals, courts and lawyers, to almost no one's satisfaction. Americans, to the extent they pay attention, seem weary of the whole enterprise. But even a president who campaigned as a peace candidate has been compelled by his daily intelligence briefings to intensify the war. And it does not end in Abbottabad.
A return to innocence is not possible without an increase in danger. With terrorism increasingly empowered by technology, pre-9/11 calculations of acceptable risk are even less responsible.
Since 9/11, however, the theory of pre-emption has been complicated by unequal development among the varieties of American power. The American military has demonstrated an unprecedented ability to decapitate a hostile regime. As President Bush put it following the fall of Baghdad, "For a hundred years of war, culminating in the nuclear age, military technology was designed and deployed to inflict casualties on an ever-growing scale. In defeating Nazi Germany and Imperial Japan, Allied forces destroyed entire cities, while enemy leaders who started the conflict were safe until the final days. Military power was used to end a regime by breaking a nation. Today, we have the greater power to free a nation by breaking a dangerous and aggressive regime."
But it has proved much more difficult to reconstruct -- or construct for the first time -- a working society once a regime has fallen. The Army and Marines have adjusted quickly to the tasks of a counterinsurgency campaign. Development assistance has increased. Yet Americans are better at humbling tyrants than at building nations. In Afghanistan there was no good alternative. But that continuing exertion has made alternatives essential in other places.
So America is left with a strategic challenge: It must pre-empt violence that takes root in failed and outlaw states without occupying and restructuring those societies. The alternative to Afghan-style nation-building is not forgetfulness and passivity. It is the development of alternative forms of American power -- working through proxies, striking with drones, promoting development, conducting covert operations. And sometimes this will mean, as President Obama has admirably demonstrated, the unilateral use of force against America's enemies.
A decade removed from 9/11, America is a sobered power but not a retreating one. Its determination reaches across administrations and to the farthest parts of the world. This continuity of American purpose is the reason bin Laden hid and the reason he died. And we can hope that, in the end, he felt the fear he loved to cause.