A non-aggression pact or neutrality pact is a treaty between two or more states/countries that includes a promise by the signatories not to engage in military action against each other. Such treaties may be described by other names, such as a treaty of friendship or non-belligerency, etc.
Leeds, Ritter, Mitchell, & Long (2002) distinguish between a non-aggression pact and a neutrality pact. They posit that a non-aggression pact includes the promise not to attack the other pact signatories, whereas a neutrality pact includes a promise to avoid support of any entity that acts against the interests of any of the pact signatories. The most readily recognized example of the aforementioned entity is another country, nation-state, or sovereign organization that represents a negative consequence towards the advantages held by one or more of the signatory parties.
In the 19th century neutrality pacts have historically been used to give permission for one signatory of the pact to attack or attempt to negatively influence an entity not protected by the neutrality pact. The participants of the neutrality pact agree not to attempt to counteract an act of aggression waged by a pact signatory towards an entity not protected under the terms of the pact. Possible motivations for such acts by one or more of the pacts' signatories include a desire to take, or expand, control of economic resources, militarily important locations, etc.
Such pacts were a popular form of international agreement in the 1920s and 1930s, but have largely fallen out of use after the Second World War. Since the implementation of a non-aggression pact necessarily depends on the good faith of the parties, the international community[who?], following the Second World War, adopted the norm of multilateral collective security agreements, such as the treaties establishing NATO, ANZUS, SEATO and Warsaw Pact.
The 1939 Molotov–Ribbentrop Pact between the Soviet Union and Nazi Germany is perhaps the best-known example of a non-aggression pact. The Pact lasted until the 1941 German invasion of the Soviet Union in Operation Barbarossa. However, such pacts may be a device for neutralising a potential military threat, enabling at least one of the signatories to free up its military resources for other purposes. For example, the Molotov–Ribbentrop Pact freed German resources from the Russian front. On the other hand, the Soviet–Japanese Neutrality Pact, signed on April 13, 1941, removed the threat from Japan in the east enabling the Soviets to move large forces from Siberia to the fight against the Germans, which had a direct bearing on the Battle of Moscow.
List of non-aggression pacts
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