Peacekeeping, a role the U.N. has played over the years, is relatively straightforward and, despite its difficulties, comparatively easy. Peacekeeping involves monitoring and enforcing a cease-fire agreed to by two or more former combatants. It proceeds in an atmosphere where peace exists and where the former combatants minimally prefer peace to continued war. Peace-enforcement, as it is used by the United States Joint Chiefs of Staff, entails the physical interposition of armed forces to separate ongoing combatants to create a cease-fire that does not exist. Boutros-Ghali, on the other hand, uses the term to refer to actions to keep a cease-fire from being violated or to reinstate a failed cease-fire. It is a subtle difference, but it does imply the existence of some will for peace. The American version more realistically portrays another, far more difficult matter. By definition, in a situation for which peace-enforcement is a potentially appropriate response, war and not peace describes the situation, and one or more of the combatants prefer it that way. This means that, unlike peacekeepers, peace enforcers are often not welcomed by one or either side(s). Rather, they are active fighters who must impose a cease-fire that is opposed by one or both combatants; in the process, the neutrality that distinguishes peacekeepers will most likely be lost.