A slew of news reports have discussed whether Snowden’s choice of Hong Kong as a haven of sorts was a wise one.  These reports tend to note the existence of a U.S.-Hong Kong extradition treaty and to describe the relatively smooth extradition practice that exists between those governments.  But the stories tend to overlook the fact that extradition is not the only means by which foreign states (or governments) can transfer people to the United States to stand trial. As the State Department’s Foreign Affairs Manual makes clear, the United States may ask other countries to return individuals to the United States by means of deportation or expulsion.  (See, for example, 7 FAM 1642 – Deportation of Fugitives to the United States.) This is particularly viable where the wanted person is a U.S. national. According to the FAM, U.S. authorities set this type of request in motion as follows: The Department of Justice gives the Department of State a copy of the arrest warrant for the fugitive and asks State to revoke the fugitive’s passport.  After State revokes the passport, it notifies the U.S. Embassy (or, in a case such as Hong Kong, the U.S. consulate) in the country in which the fugitive is located. The Embassy or Consulate then approaches the host government with a request for expulsion or deportation, if such a process is authorized by the host government’s laws.

Ashley S. Deeks, Safe Haven(s) for Snowden?, Lawfare (June 10, 2013).