There was no formal declaration of war during the Cold War

The argument

A formal argument that the Cold War was not truly a war is that it lacked the defining legal and political marker of one: a declaration of war. Throughout the roughly forty-five years of the Cold War, neither the United States nor the Soviet Union ever formally declared war on the other. War, in the established sense recognised by international law and historical convention, is a legal state of armed hostility between nations, typically initiated by a formal declaration and governed by the laws of war. The Cold War had no such declaration, no legal state of war between the two superpowers, and no point at which either nation announced itself to be at war with the other. The argument holds that this absence is not a technicality but a reflection of the conflict's real nature. The two powers never entered the formal condition of belligerency that defines war; they remained, in legal terms, at peace with one another throughout, however hostile their rivalry. They maintained diplomatic relations, signed treaties, held summits and negotiated arms-control agreements with each other — conduct characteristic of nations that are rivals but not at war. A genuine war between them would have meant a declared state of armed conflict, mobilisation against each other and the legal apparatus of belligerency, none of which ever existed. From this standpoint, calling the Cold War a 'war' is a metaphor rather than an accurate description. It was an intense geopolitical rivalry and ideological competition, but it never crossed the formal threshold — marked by a declaration of war — that distinguishes an actual war from a tense peace. Because there was no formal declaration of war between the superpowers, this argument holds, the Cold War should not be considered a war.

Premises

Counter-arguments

Critics argue that a formal declaration is not what makes something a war. Many conflicts universally recognised as wars — Korea, Vietnam, numerous others — were fought without any formal declaration, and the requirement of a declared state of belligerency has largely fallen away in modern practice. If undeclared conflicts still count as wars, the absence of a declaration cannot by itself disqualify the Cold War. They add that the Cold War had much of war's substance even if not its legal form: a decades-long arms race, a global contest fought through proxy wars in Korea, Vietnam, Afghanistan and elsewhere in which the superpowers armed and sometimes directed the combatants, pervasive espionage and covert operations, and moments such as the Cuban Missile Crisis that brought direct armed confrontation close. 'War' is meaningfully used for sustained, organised, existential hostility, they contend, not only for a narrow legal condition — so treating the Cold War as a war captures its reality rather than merely speaking in metaphor.

Rejecting the premises

[Rejecting P2] Critics note many acknowledged wars (Korea, Vietnam) had no formal declaration, so a declared legal state of hostility is not the defining criterion of war. [Rejecting P3] Diplomatic relations coexisted with an arms race, proxy wars and near-direct confrontation like the Cuban Missile Crisis, so maintaining treaties and summits does not show the two powers were simply 'at peace.'