At what point shall we expect the approach of danger? By what
means shall we fortify against it? Shall we expect some
transatlantic military giant, to step the Ocean, and crush us at
a blow? Never! All the armies of Europe, Asia and Africa
combined, with all the treasure of the earth (our own excepted)
in their military chest; with a Buonaparte for a commander, could
not by force, take a drink from the Ohio, or make a track on the
Blue Ridge, in a trial of a thousand years.

—Abraham Lincoln, Address before the Springfield Young Men’s
Lyceum, 1838

Are we to think that September 11 proved Lincoln wrong? Certainly,
there are many Americans who now feel vulnerable. In losing their
sense of security, they may also have lost their sense of
American exceptionalism. While it might have been true that
America was once geographically blessed, our moated fortress is
no longer unbreachable. Nature’s gift has been undone by our own
technological ingenuity. It does not even require an
intercontinental ballistic missile to “step the Ocean”—an
airplane will do. A few foresighted observers had long (and
unavailingly) warned that the advances of modernity might be
turned against us by anti-modern crusaders who would take a sick
delight in the irony of such death-dealing. It seems that in the
future our protection will depend more on ourselves than on
Providence, and will largely be a matter of defending ourselves
against the vicious application of our own