For those making snarky comparisons to "eating food" or "waking up in the morning"...<p>If I had a group of people, and wanted to find out the terrorist, which would be a more useful metric for raising my probability of discovering them?<p><pre><code> 1. The person eats food
2. The person wakes up in the morning
3. The person uses the dark web
</code></pre>
It doesn't mean everyone using the dark web is a terrorist -- but no one said that. It means that it's a useful metric when trying to spot terrorists.<p>Pair it with other useful metrics and you have a good algorithm for who to keep an eye on.