"In its 2013 financial statements, the Tor Project - a group of developers that maintain tools used to access Tor - confirmed that the US Department of Defense remained one its biggest backers. The DoD sent $830,000 (£489,000) to the group through SRI International, which describes itself as an independent non-profit research centre, last year. Other parts of the US government contributed a further $1m. Those amounts are roughly the same as in 2012."
I'm not familiar at all how those founding works, could someone, from US, explain how and why US government is giving money to TOR?