This unit test will fail when developer.usa.gov/1usagov shuts down.  Or when it is run on a machine that is behind a firewall and not allowed to talk to the world at large.

A unit test that fails because of some external behavior is not good.  Unit tests should only fail when the code is wrong and should fail under no other conditions.  This generally means that a unit tests should *never* make a connection to something that it is not running on its own.