The events of Sept. 11 proved two things, among many others: that we are all linked inextricably, and that in this country at least, optimistic thinking will assert itself, even in the face of disaster. The linkages were immediately evident, of course, from the moment disaster struck — grounded airplanes meant a halt in air shipments, meaning a sudden interruption in a seafood market that in a quarter-century has become truly global. Heightened security continues to affect everyone, putting civil liberties at risk.

Yet as we responded to new threats with legislation, executive orders and military action, Americans’ instinctive optimism began to re-emerge. We looked at our problems, old and new, and went back to work on them as we always have. We asked questions, and we began to craft answers to them. We know now, having been brutally reminded, that we can no longer feel shielded from the rest of the world. But because we are essentially optimistic, we can face the future confident that we will meet its challenges. It’s not a holiday message anyone would have chosen, but it’s one that inspires us all the same.