Security dilemma
In that example, strategists believed that offense would be more advantageous than defense, but that ultimately turned out to not be the case. Competition on nuclear weapons construction between the United States and the Soviet Union, during the Cold War, is a well-known example of an arms race.

Alliance formation: The security dilemma might force states to form new alliances or to strengthen existing alliances. "If offense has less advantage, stability and cooperation are likely". According to Glenn H. Snyder, under a security dilemma there are two reasons that alliances will form. First, a state that is dissatisfied with the amount of security it has forms alliances in order to bolster its security. Second, a state is in doubt about the reliability of existing allies in coming to its aid, and thus decides to court another ally or allies. According to Thomas Christensen and Jack Snyder, in a multipolar world two types of alliance dilemma exist which are contrary in nature. These alliance dilemmas are known as chain ganging and buck passing.

Chain ganging: In a multipolar world, alliance security is interconnected. When one ally decides to participate in war, it pulls its alliance partners into the war too, which is referred to as chain ganging. If the partner does not participate in the war fully, it will endanger the security of its ally. For example, in World War I, to the alliance between Austria-Hungary and Germany, according to Waltz, did this: "If Austria-Hungary marched, Germany had to follow: the dissolution of the Austro-Hungarian Empire would have left Germany alone in the middle of Europe". On the other side, if "France marched, Russia had to follow; a German victory over France would be a defeat for Russia. And so it was all around the vicious circle, because the defeat or defection of a major alliance would have shaken the balance, each alliance partner would have shaken the balance, each state was constrained to adjust its strategy".

Buck passing: In the face of a rising threat, balancing alignments fail to form in a timely fashion as states try to freeride on other states. States might do so to avoid the expense of war for themselves. For example, to use Waltz's example, in World War II, the French Foreign Minister told the British Prime Minister that Britain was justified in taking "the lead in opposing Germany" when the Nazis had taken over the Rhineland, but as "the German threat grew", France and Britain hoped that Germany and the Soviet Union "would balance each other off or fight to the finish. Uncertainties about... who will gain or lose from the action of other states accelerate as number of states increases".

Criticisms and responses: According to Alexander Wendt, "Security dilemmas are not given by anarchy or nature" but, rather, are "a social structure composed of intersubjective understandings in which states are so distrustful that they make worst-case assumptions about each other's intentions". Jennifer Mitzen mirrors Wendt's critique, arguing that the security dilemma can be caused and maintained by the pursuit for ontological security rather than rationalist security-seeking.
Glaser argues that Wendt mischaracterised the security dilemma. "Wendt is using the security dilemma to describe the result of states' interaction whereas Jervis and the literature he has spawned use the security dilemma to refer to a situation created by the material conditions facing states, such as geography and prevailing technology". According to Wendt because the security dilemma is the result of one state's interaction with another, a state can adopt policies which hinder the security dilemma. Glaser blames Wendt for "exaggerating the extent to which structural realism calls for competitive policies and, therefore, the extent to which it leads to security dilemmas". Glaser argues that though offensive realists presume that in an international system a state has to compete for power, the security dilemma is a concept mainly used by defensive realists and according to defensive realists it is beneficial for nations to cooperate under certain circumstances.
Another mode of criticism of the security dilemma concept is to question the validity of the offence-defense balance. Since weapons of offense and of defense are the same, how can the distinction between the two be connected with a state's intentions? As a result, critics have questioned whether the offense-defense balance can be used as a variable in explaining international conflicts. 
According to Charles Glaser, criticisms of the offense-defense balance are based on two misunderstandings. First, the sameness or difference of offensive weapons compared with defensive weapons does not impact the offense-defense balance itself. Offense-defense theory assumes that both parties in conflict will use those weapons that suit their strategy and goals. Second, whether both states involved in the conflict have some common weapons between them is the wrong question to ask in seeking to understand the offense-defense balance. Instead, critics should focus on the influence or net effect of weapons used in the conflict. According to Glaser, "Distinguishability should be defined by comparative net assessment" or the comparison of the balance of offense-defense when both sides use weapons versus when neither side is using weapons.

See also: Balance of power in international relations
Escalation of commitment
Hobbesian trap
Red Queen's race
Prisoner's dilemma


== References ==