"In times of war, belligerent countries can be contrasted with neutral countries and non-belligerents. However, the application of the laws of war to neutral countries and the responsibilities of belligerents are not affected by any distinction between neutral countries, neutral powers or non-belligerents. A non-belligerent may nevertheless risk being considered a belligerent if it aids or supports a belligerent in a way proscribed by neutral countries.

An interesting use of the term arose during the American Civil War, when the Confederate States of America, though not recognized as a sovereign state, was recognized as a belligerent power, and thus Confederate warships were given the same rights as United States warships in foreign ports."

http://www.reference.com/search?r=13&q=Belligerent

Being on the defensive is still combat. As noted, this status protected the Confederate Army. Stan