War has long been the central issue in international relations, even in those years in which no active war was being pursued. Recently the situation has been confused by declaring a "war on terrorism", a concept that needs to be addressed by thinking more carefully about what we mean by war and terrorism, how they may be initiated, fought, and brought to an end.

"War" traditionally has referred to a violent struggle between two or more contesting groups. Such a war is assumed to have a beginning and an end. The problem with understanding what is meant by a "war on terrorism" is that terrorism is a concept or condition whose frequency and intensity waxes and wanes throughout history. Sometimes it is directed against one group or government, sometimes another. In these terms a war by the United States against a particular group employing terrorism, such as Al Qaeda, makes sense, but a war against a concept does not. One of the problems with the latter, of course, is that it is likely to be never-ending. This is particularly dangerous to an advanced state with protections against government encroachment on rights, because since all states restrict freedoms during emergencies such as war the end result of a "war against terrorism" may well be a never-ending restriction of freedoms (as in 1984).

Genocide is a useful term for a particularly horrendous form of violent struggle, but since the holocaust it has been so frequently employed as to lose much of its meaning. In spite of the broad dictionary definition (accompanying), it should be understood only to refer to the intentional destruction of a particular ethnic (racial and/or cultural) group by another group (often one dominating the government in power). The decision of the top levels of the German government immediately before and during World War II to destroy Jews and Gypsies (and to a lesser extent Slavs) is properly seen as genocide. The struggles of the Hutus and Tutsi have often been genocidal, as were aspects of the struggles in the former Yugoslavia.

However, the destruction of millions of "Kulaks" (land-owning farmers) in the USSR, or of millions of relatively wealthy Chinese or Cambodians by Communist regimes deserve another term. (R. J. Rummel refers to these cases as "politicide", and groups them together with genocide as "democide". To find out more about his work go to Rummel's web site.) Even more doubtful is careless use of "genocide" to refer to most of the suppression and depression of African-Americans in the United States. The fact that the effects look like genocide does not legitimize the use of the term without majority group intent. (Some incidents have no doubt been genocidal, however, as have some actions against American Indians along the frontier.) Most plays on the word, such as "ecocide", while evocative should be limited to only the most legitimate parallels to genocidal violent conflict among human beings.

Guerrilla War varies from a form of conventional war (with uniforms, the taking of prisoners, field hospitals, and the observance of Geneva Conventions on both sides) to widespread resort to terrorism on both sides. It is particularly difficult for a relatively weak guerrilla force to maintain the conventions of war. Yet if it does not, it justifies to some extent the flaunting of the conventions by its conventional opponent. For example, in so far as its "soldiers" melt into the population by day, the general population becomes "the enemy". Persons not in uniform and pretending not to be combatants come to be considered common murderers and may be treated as such rather than prisoners of war. These remarks cannot be taken as justification for "illegal actions" in counter-guerrilla warfare, but they must be considered in judging those engaged in violence at this level.

Distinctions among forms and types of violence are particularly important when we remember that all states, including even the United States,must operate in the world with reference to international law, and we must fight our wars and compel others in so far as possible to fight their wars, in terms of the laws of war), especially those specified by the Geneva Conventions.

In the discussion of war, we need also to be clear about what we mean by strategy and tactics. A strategy is a general overall plan to achieve a common objective; a tactic is a means that will be used to obtain that objective. The problem is essentially that at each succeeding level of discussion the strategy of the previous level tends to become the tactics of the next level. Working from the top down, the strategy of the U.S. Government during the Cold War was to prevent nuclear war by possessing such a strong deterrent ability to respond that the USSR would not launch an attack. The strategy of our top military leaders was to attack Soviet nuclear weapons as soon as possible when war was imminent or underway, so as to prevent their use. The strategy of units of the air force that were to be used to achieve this objective might be to fly B-52s at treetop level to get under Soviet radar. From the top down such plans would be considered "tactical", but at their own level could be seen as a "strategy".