The Long War between Islam and the West began roughly a thousand years ago. It has flared up from time to time and gone quiet from time to time. Don't kid yourself, it has not ended. This is a lull, not a truce.
What happened 22 years ago today at the World Trade Towers, the Pentagon, and a field in Pennsylvania was another of its flare-ups, one noted for its spectacular nature and near-instantaneous large loss of life.
There are those who understand this, and those who choose not to admit it to themselves. On this sad anniversary, understand and remember.