The date September 11th is clearly engraved on our minds as the date of the terrorist attacks in New York, Pennsylvania, and Washington. Whether you characterize the Islamic terrorists as "non-Christian" or "anti-Christian", in either case, they believed themselves to be attacking a nation which they believed to be spiritually corrupt. They were attacking a nation whose core values (freedom, equality, individualism) were opposed to their worldview.
But there is another September 11th, over a century earlier. In 1857, a group of Christian families were making their way westward as part of a wagon train. Consisting largely of farmers with their wives and children, they had begun in Arkansas, and were mid-way through Utah on their journey toward California. Unfortunately for them, this was at time when the Mormon Church (also known as "Latter-Day Saints") was feeling somewhat paranoid toward the ordinary population of the United States. Convinced that these peaceful civilians posed some threat, the wagon train was attack at a location known as "Mountain Meadows", where over one hundred men, women, and children were slaughtered. Only a few infants remained alive. The Mormons had been ordered not only to attack the Christians, but to ensure that all of them died.
Whether in 1857 or in 2000, September 11th reminds us that the worldview of Western Civilization - a worldview that values each human life greatly and equally - is a culture which will has been attacked by other traditions - traditions which don't place much emphasis on the dignity of the individual human.