From a brute-force PoV, I imagine you can have armed FBI agents in the offices of major ISPs in an hour or so. If they block their customers and they also bloc

From a brute-force PoV, I imagine you can have armed FBI agents in the offices of major ISPs in an hour or so. If they block their customers and they also block their resellers, then really you can handle most of the Internet with probably a dozen 2-man teams. It's not really that critical if it's deemed too hard to block two guys on the same local ISP from chatting. Not to mention that even rudimentary steps - knocking out DNS or even just Google, Yahoo, and Bing - would put 95% of Americans effectively offline. Metcalfe's Law works both ways - if you cut off even 3/4 of the internet, it's now only a square-root of a square-root as valuable as it used to be.