I think before 9/11 most of the country had a "we are America and untouchable" outlook. A "a major terrorist attack could never happen here," kind of thinking. Of course it only makes sense then that some people would still think it couldn't have happened unless it was an inside job. Well, we have an open border with Mexico that isn't policed as it should be and people are coming across it all day every day. News flash. They're not all Mexican coming across that border. Many are from China, Korea, various countries of the middle east. If you think there's not terrorists in this country just waiting for an order to do something terrible again, your dead wrong.
Today we should remember those that lost their lives that terrible day, and the bravery of those who responded. Every day for the rest of the year we should stay vigilant and understand that if this happened once before, it can and likely will happen again. Especially if we bury our heads in the sand or believe it will never happen to us.