organizational warfare

OK, so here are some questions. Can an organization “declare war on a country”? Can a person, citizen or not, “declare war on a country”? If a person joins an organization that has declared war on a country, may the country consider him to be an enemy combatant? Of course they can make the statements or take actions that make the statements for them. But does the country have the right to treat that as a war situation? What are the rights of and permissible actions available to the country in that situation? Can it take them at their word and treat them an “enemy combatants”? If they hide in dark alleys in foreign countries can it go there and kill them? If the answer is yes then what kind of procedure should a government go through before they put someone on that “kill or capture list”?
Obama has a kill or capture list and Awlaki is on it. The left is finally starting to ask questions about it. This is the same left that went berserk when Bush poured water in the faces of known terrorists but ….