Saad Hariri, who became prime minister for the second time less than a year ago in a government of national unity, cited the dominance of Lebanon by Iran and its ally Hezbollah and threats to his life as being behind his decision to resign.
Hezbollah says it's fighting alongside government forces in Syria to prevent violence from coming home to Lebanon. Some in Lebanon say Hezbollah is the one bringing the violence home.
US relations with Iran have never completely recovered from the seizure of American hostages at the US embassy in Tehran in 1979.