This is an important and provocative post from David Kopel. I need to add this to my 2301 lecture on natural rights. The author quotes a variety of classical authors who make arguments against the legitimacy of tyrannical governments, likening them to robbers. A tyrannical government is not a legitimate government. That statement should make sense if you properly understand the argument made in the Declaration of Independence.
Consider this required reading.
Obviously the post relates to current issues regarding Libya, but it gives no hint about what pragmatic steps can be taken to deal with tyrannical governments. Is there an obligation to remove them from power?