DEFENSIVE REALISM THEORY                Defensive realism is an umbrella term for several theories of international politics and foreign policy that build upon Robert Jervis's writings on the security dilemma and to a lesser extent upon Kenneth Waltz's balance-of-power theory (neorealism).                Defensive realism holds that the international system provides incentives for expansion only under certain conditions. Anarchy (the absence of a universal sovereign or worldwide government) creates situations where by the tools that one state uses to increase it security decreases the security of other states.              This security dilemma causes states to worry about one another's future intentions and relative power. Pairs of states may pursue purely security seeking strategies, but inadvertently generate spirals of mutual hostility or conflict. States often, although not always, pursue expansionist policies because their leaders mistakenly believe that aggression is the only way to make their state secure.              Defensive realism predicts great variation in internationally driven expansion and suggests that states ought to generally pursue moderate strategies as the best route to security. Under most circumstances, the stronger states in the international system should pursue military, diplomatic, and foreign economic policies that communicate restraint.               Examples of defensive realism include: offense-defense theory (Jervis, Stephen Van Evera, Sean Lynn-Jones, and Charles Glaser), balance-of-power theory (Barry Posen, Michael Mastanduno), balance-of-threat theory (Stephen Walt), domestic mobilization theories (Jack Snyder, Thomas Christensen, and Aron Friedberg), and security dilemma theory (Thomas Christensen, Robert Ross, and William Rose). (Sources: Jeffrey W. Taliaferro, 'Security-Seeking Under Anarchy: Defensive Realism Reconsidered,' International Security, 25, 3, Winter 2000/2001: 152-86; and John J. Mearsheimer, (2002), Tragedy of Great Power Politics, W.W. Norton, New York).

DEMOCRATIC PEACE THEORY              All democratic peace theories seek to explain the disputed empirical fact that two constitutional democracies have never gone to war with each other in recent history (1816 onwards). As such, they rest on a similar hypothesis: that relations between pairings of democratic states are inherently more peaceful than relations between other regime-type pairings (i.e. democratic versus non-democratic or non-democratic versus non-democratic).               To prove the reality of the democratic peace, theorists such as Michael Doyle have sought to show a causal relationship between the independent variable - 'democratic political structures at the unit level' - and the dependant variable - 'the asserted absence of war between democratic states'. Critics, such as Ido Oren, dispute the claims of democratic peace theorists by insisting that there is a liberal bias in the interpretation of 'democracy' which weakens the evidence.

DEPENDENCY THEORY                 Dependency theorists assert that so-called 'third-world' countries were not always 'poor', but became impoverished through colonial domination and forced incorporation into the world economy by expansionist 'first-world' powers.                Thus, 'third-world' economies became geared more toward the needs of their 'first-world' colonial masters than the domestic needs of their own societies. Proponents of dependency theory contend that relationships of dependency have continued long after formal colonization ended.                Thus, the primary obstacles to autonomous development are seen as external rather than internal, and so 'third-world' countries face a global economy dominated by rich industrial countries. Because 'first-world' countries never had to contend with colonialism or a world full of richer, more powerful competitors, dependency theorists argue that it is unfair to compare contemporary 'third-world' societies with those of the 'first-world' in the early stages of development.