Thanks for finding all of those sources. That is indeed a vast network of intercepts, however it's not necessarily "global" in the sense that they monitor all communication. If one could choose their Tor link to include enough paths not likely to be monitored by colluding parties, then one could be more certain they are not facing a "global adversary" in the sense that the Tor site means.
Not literally all communication in the global sense that Tor refers to. For a trivial example, the wifi signal between my computer and my router is not monitored.
Your references seem to talk about major exchanges all over the globe. Practically speaking, because a Tor client can choose the routers for the link it creates, it could choose three routers behind a single major exchange that is monitored (e.g. in Asia or South America), and hence remain anonymous, because the connections between those routers are not monitored.
because the connections between those routers are not monitored
A correlation attack[1] doesn't care about the intermediate routers. It only requires packet dumps from the entry and the exit node. Both of which, with very high probability, route through networks that are monitored by the NSA.
Good point. I wonder how useful that is in practice with the amount of traffic going through the Tor network. It seems to me that the more people use it, the harder it would be to get accurate correlations. That said, I wouldn't be surprised if some clever math can do so more accurately than has been published.
