After 11 years, through searing pain and gradual healing, this remains a day we cannot, and should not, forget.
It is easier today than it was years ago to relegate the memories of Sept. 11, 2001, to a psychological storage vault, where they don't impinge on our lives. But as the day approaches - the temperatures cooling, the light falling at a late-summer angle, the sky taking on that crystal shade of blue - the memories break out again.
As well they should. The thousands of victims deserve no less than to be remembered by the nation that was the true target of those attacks.
That's why a memorial and museum in the footprint of the twin towers is important and even necessary. At a time when we frequently seem to be on memorial-building autopilot, this is one that indisputably demands to exist.
Whether it demands to exist in the way it was designed may be another question. With annual upkeep costs of about $60 million, the 9/11 memorial and museum will be many times more costly than those at Pearl Harbor ($3.6 million) or Gettysburg ($8.4 million), neither any less deserving. And that cost doesn't even include the expense of operating the two massive fountains that mark the spots where the skyscrapers once stood. That adds another $5 million.
There are differences in those national memorials, of course, mainly in the level of security officials believe is needed at the 9/11 memorial. They point out that the World Trade Center was the target of two attacks and that the memorial to world terror's high water mark might be a tempting target, itself. It's not unreasonable.
Still, many people, including supporters of the memorial, worry that the expense is too high - either as a defensible amount of money for its purpose, or as a cost that can be sustained in perpetuity.
It is a worrisome figure and even if the point has been rendered moot - the memorial is complete, although the museum is not - it raises difficult questions that Americans should ask themselves.
Are we, perhaps to assuage our own pain, committing future generations to an expense that will be hard to manage? How much is too much in honoring the victims of an infamous attack of severe and long-lasting consequences? Does $60 million a year cross that line or, given the circumstances, is it plausible? Is grander always better?
Such questions are hard to grapple with in connection with an event as shattering as the 9/11 attacks.
In the meantime, Americans will stop again today to recall that devastating event. It's a different world, 11 years later. We haven't been attacked again, thanks to some combination of government attention, public awareness and luck, but we know the threat exists.
The best thing we can do now for the victims of 9/11 is to do all that a democracy reasonably can to prevent others from suffering their fate - and to pursue the ideals for which this country stands.