What we've learned from the British experience is that if people are admonished to notify authorities of suspicious activity or abandoned parcels, if you then readily have communications systems for them to do that -- telephones that are marked -- and you provide rapid response when reports are made, then in effect you have closed the loop.
That means that as opposed to waiting for full-fledged conspiracies, they may be picking up individuals when they are still in the early part of this recruiting trajectory. They may have only taken a few steps down the path. But if you're going to wait until there are mature terrorist plans, then that runs a risk. And in this post-911 environment, authorities are unwilling to take that risk.
The Internet gives them direct access. It even allows them to segment their audiences so they can communicate with potential recruits, with those who are already in the organization, and with broader sympathetic audiences as well as their enemy. They can do ... modern marketing and these communications have enabled them to be very, very effective and they've been increasingly adept in exploiting this. I don't think we have yet fully fathomed the sophistication of their communication strategy.