Remembering won't bring back the dead. Remembering won't change the past. Remembering won't stop it from happening again. Last of all, dedicating a day of remembrance isn't respecting those who lost their lives - it's making idols out them.
Ideally, you learn what you need to from an event, and then take those lessons and apply them to the future to keep something like that from happening again. Those who lost people close to them can grieve at any time. The vast majority of the nation who weren't personally affected at all are better off focusing their energy in productive, and positive ways.
But instead we get the event glorified. We prop the dead onto pedestals, regardless of their will and use them as undead martyrs of sorts to push religious and political ideology. We hate those who committed the act, and by typical human nature extend that hate irrationally to broader groups of people that had nothing to do with the event.
I can't say that what you are saying here is factually incorrect. But I disagree with it nonetheless.
In Canada, each year, on November 11, we dedicate a day to remember our fallen soldiers. Some have argued that this should be a day to remember the wastefulness of war, a day to remember the importance of peace.
But I, for one, was perfectly happy with that day the way it used to be.
Not as a day to stir up hatred for Germans. But as a day to remember the sacrifice of those who died to defend the freedom of countries like France and Belgium and South Korea. A day to be reminded that "freedom isn't free".
Because if we decide that fighting in wars is just too much bother, we won't survive very long as a free nation.
Yes, you are quite right that apparently apolitical public, organized mourning for those who perished on September 11, 2001 is likely to serve a "political agenda". The agenda of muting criticism and controversy over the wars in Afghanistan and Iraq. The agenda of instead uniting the nation behind whatever it may be called upon to do to prevent future acts of terrorism, to bring those responsible for past acts of terrorism to justice, to root out whatever it is that is the source of terrorism.
So that, when we're done, not only Americans and Britons and Spaniards will feel safe and secure, with the threat of a terrorist attack once again something impossibly remote, but the people of Israel, and even the people of the southern Sudan, the people of Somalia, the people of Nigeria will fully share in this good fortune.
On December 7, 1941, the Japanese bombed Pearl Harbor. The nation remembered those who fell there, and it continued its efforts until Imperial Japan was completely defeated, and all those it had subjugated were freed.
This was as it should be.
Similarly, the nation should remember those who fell on September 11, 2001, and continue its efforts until the forces of terrorism are completely defeated, no longer a problem for anyone.
I don't see how that's a problem, or even a choice. As it always was, so shall it ever be: for a nation to survive in peace, it must commit itself to utterly crush those who would dare to attack its peaceful citizens. If, instead, a nation's citizens can be attacked with impunity, collapse is imminent.
