When Americans went to sleep on Sept. 10, 2001, they were expecting to wake up to just another day. Until 2001, Sept. 11 was a day like any other — a day when people celebrate birthdays, land a new job, mark an anniversary or attend a funeral. It was just another day.

But on the morning of Sept. 11, 2001, Americans watched live television footage of the disaster unfolding. And as terrible as the images were, the scene was made worse by the disturbing lack of solid information about what was happening and where.

All of America — and the world — struggled to understand the chaos surrounding the coordinated attacks that killed some 3,000 people in New YorkCity, Washington, D.C., and on a plane that crashed in rural Pennsylvania.

Four flights originating from East Coast airports were hijacked by members of a then little-known group called al-Qaida.Two passenger jets were smashed into the twin towers of the World Trade Center in New York and a third was flown into the side of the Pentagon.The fourth plane is believed to have been heading for the White House or U.S. Capitol, but the passengers who had learned of the earlier suicide attacks battled to take over the aircraft, and it crashed into a field near Shanksville, in Somerset County.

Time will help clarify what Sept. 11 comes to mean. But, it will never again be just another day, a day of birthdays and anniversaries. It will always be remembered as a day when everything changed. But how — and for how long — things have changed is still not known.

For most Americans, daily life is not dramatically different today than it was on Sept. 10, 2001. But taking a commerical flight anywhere in the country or overseas offers a quick reminder of how much things have changed. And, the untold billions of dollars of taxpayers' money being spent on anti-terrorism and first-responder efforts, with varying degrees of legitimacy and effectiveness, are another reminder.

Some analysts will argue that al-Qaida is attacking the U.S. effectively every day that we spend money trying to thwart future attacks. Despite the billions of dollars already being spent and the billions more that would have to be spent to truly secure the borders and screen every container and ship coming into ports, and check every vehicle coming into the U.S. and every plane arriving at domestic airports, it seems likely that someday another attack will succeed.

Determining the best approaches to fighting terrorism provides legitimate topics for serious debate. But, this year, and possibly for years to come, Sept. 11 and the war on terror is drenched in politics.

That's unfortunate, but it also is predictable. Politics was largely absent in the days following the attacks, but since that time there has been deep disagreement over how the nation should respond to the attacks and what should be done to prevent future attacks.

That disagreement is sometimes genuine and sometimes partisan. When it is genuine, it is useful. When it is partisan, it is not. And these days, it is mostly partisan.

But regardless of how the political winds blow, Sept. 11 will be remembered as a day when the world changed.

Not long after the attacks, commentators talked about change and how the best that Americans could expect would be acceptance of what was called "the new normal."

This week, commentator Leonard Pitts Jr. suggested that pre-9/11 days are now seen as the "good old days" and reminded readers that you don't recognize the good old days until they are gone. Pitts also suggested America was innocent on Sept. 10, 2001. But, Pitts writes, "we had not yet seen people jumping from flaming skyscrapers. We had not yet seen office towers crumble to the ground on live television. We had not yet seen dust-caked people wandering the streets of our greatest city."

Pitts and other skilled commentators in print and on television will give us much to think about on the anniversary of the Sept. 11 attacks.

The reflection taking place at this time of the year is healthy, if frustrating. The challenge of global terrorism is a hard concept to grasp, particularly in a time of lethal chemical and biological weapons, suitcase-size nuclear bombs and so-called dirty bombs that spread deadly radioactive waste using conventional explosives.

It no longer takes another nation's army, navy or air force to attack America. A loose collection of a very small number of determined people with relatively little money can cause immeasurable destruction to the most powerful nation in the world. It's a sobering and depressing thought that America and the world will wrestle with for years to come.