So 'tacit consent' is quite likely indeed.
[1] https://bitcointalk.org/index.php?topic=6652.msg146198#msg14...
edit - I mispoke regarding location, it was the CIA HQ. However, the 'emerging technologies conference' was for the broader US intelligence community.
I think it's also worth noting that covert agencies may find benefits of their own in a public global system for moving money around quickly, verifiably, irreversibly, and somewhat anonymously.
"Tor was originally designed, implemented, and deployed as a third-generation onion routing project of the U.S. Naval Research Laboratory. It was originally developed with the U.S. Navy in mind, for the primary purpose of protecting government communications. Today, it is used every day for a wide variety of purposes by normal people, the military, journalists, law enforcement officers, activists, and many others." https://www.torproject.org/about/overview.html.en