In the new paper "Terrorism and Civil War: A Spatial and Temporal Approach to a Conceptual Problem" published in Perspectives on Politics (June 2012), Findley and Young write:
The data show a high degree of overlap between terrorism and ongoing civil war and, further, indicate that a substantial amount of terrorism occurs prior to civil wars in Latin America, but yet follows civil war in other regions of the world.
The author take a long term perspective and look in detail at cases like Argentina, Peru, El Salvador, Lebanon, Mozambique, and others.
A graph from the paper:
A draft is here (2010).