Captain Ed has a point:

As the NIE noted, jihadist websites provide both indoctrination and operational capabilities for jihadists around the world. It should be in America’s interest to get these sites shut down. Who do we have to invade for victory on this front? Apparently, Texas, Nevada, New Jersey, and Washington:

UPDATE: An e-mailer makes good points:

If identified and monitored, these sites can be valuable sources of
intelligence for the U.S. It is possible, for instance, to hack into
the site and download the addresses of all those who have accessed
the site, then cross reference them with other, similar sites,
terrorist watch lists, etc. One can also use such sites for
disinformation by uploading spurious materials onto them. And if it
is necessary to take down a site, it is not necessary to go through
the ISP or to take any sort of formal legal action; merely infect the
site with a really good virus, and pretty soon its habitues will
avoid it like the plague. And, in the meanwhile, they’ll be
transmitting the virus to their fellow jihadis, gradually bringing
the JihadWeb to a crashing halt. In the CyberAge, use CyberTactics.