Too soon, really, since most countries engaged in Afghanistan are still there, even the Dutch and Canadians who left in one form (combat) and came back in another (training). As I was traveling from Dublin to London, twitter was chock full of Afghanistan war anniversary commentary--that the US started its campaign on October 7th, 2001. Here is my quick take (as I am about to start Steve-talk-apooloza in London [evacuations have apparently begun)].
First, yes, eleven years is a long time. It is longer than two world wars combined (especially the US's shorter involvements in those conflicts), but it is not as long as the American effort in Vietnam. More importantly, these comparisons are both instructive and confusing. They are confusing because the US has committed far less of its attention, its military capability, and everything else to Afghanistan. US forces briefly peaked at something over 100,000. The US had five times that in Vietnam. While the US has spent billions and billions, the spending again pales compared to previous wars as a share of GDP. The US should have been more committed to the effort in 2003-2009, but it was distracted by Iraq. We have lots of ifs, but it does seem pretty certain that being distracted and undercommitted mattered a great deal.
Second, someone noted on twitter that the Afghans are not really marking this anniversary. Why should they? Their war started in ... 1979 when the Soviet Union invaded. After the USSR left after doing incredible damage, civil war broke out that did not end with the rise of the Taliban. It might have ended in 2001 since 9/11 was preceded by the assassination of the Northern Alliance's most significant leader, Massoud, two days earlier. So, 11 years of the US hanging around is not quite as significant as 42 years of violence.
Off to my morning meeting! Cheerio!