Here's one scenario: You can be identified that you are using Tor, at your ISP end. If it is acceptable for your ISP to provide information about the connectio

Here's one scenario: You can be identified that you are using Tor, at your ISP end. If it is acceptable for your ISP to provide information about the connections you are making (the metadata) to the authorities without warrant, then the authorities can gather a list of citizens who use Tor. They might then convince a kangaroo court that using Tor is enough cause to suspect criminal activity such that the court issues a warrant for further direct surveillance, or to seize your computers. Then you could be jailed until you reveal your encryption keys, or the direct surveillance could catch you in the act. All this could happen even if you're doing nothing illegal on Tor. Does this seem far fetched? Given recent events, it seems that potential adversaries don't have a problem with: 1) Gathering data en-masse without warrant (eg. this recent event). 2) Convincing courts that you're doing illegal things based on tenuous information that they've gathered, without any further oversight (eg. IP addresses participating in a BitTorrent stream). 3) Arranging for your computer equipment to be seized on trumped up charges, even if you're in a different jurisdiction (eg. Kim Dotcom). 4) Forcing you to reveal your encryption keys, under threat of jail (law in the UK; precedent set in some jurisdiction in the US, although AIUI the Supreme Court may eventually overrule).