An undeclared war is a
military conflict
War is an intense armed conflict between states, governments, societies, or paramilitary groups such as mercenaries, insurgents, and militias. It is generally characterized by extreme violence, destruction, and mortality, using regu ...
between two or more nations without either side issuing a formal
declaration of war
A declaration of war is a formal act by which one state announces existing or impending war activity against another. The declaration is a performative speech act (or the signing of a document) by an authorized party of a national government, ...
. The term is sometimes used to include any disagreement or conflict fought about without an official declaration. Since the
United Nations
The United Nations (UN) is an intergovernmental organization whose stated purposes are to maintain international peace and security, develop friendly relations among nations, achieve international cooperation, and be a centre for harmoni ...
police action in
Korea
Korea ( ko, í•œêµ, or , ) is a peninsular region in East Asia. Since 1945, it has been divided at or near the 38th parallel, with North Korea (Democratic People's Republic of Korea) comprising its northern half and South Korea (Republic ...
,
a number of democratic governments have pursued disciplinary actions and limited warfare by characterizing them as something else such as a military action or armed response.
United States
There is no specific format required under United States law for the way an official war declaration will be structured or delivered. The United States Constitution states: "The Congress shall have Power
€¦To
declare War, grant
Letters of Marque and Reprisal, and make
Rules concerning Captures on Land and Water".
As of August 2013, the
United States Congress
The United States Congress is the legislature of the federal government of the United States. It is Bicameralism, bicameral, composed of a lower body, the United States House of Representatives, House of Representatives, and an upper body, ...
has formally declared war 11 times, and has not done so since 1942; 6 of these were WWII declarations.
The United States did not declare war during its
involvement in Vietnam, although the
Gulf of Tonkin Resolution
The Gulf of Tonkin Resolution or the Southeast Asia Resolution, , was a joint resolution that the United States Congress passed on August 7, 1964, in response to the Gulf of Tonkin incident.
It is of historic significance because it gave U.S. p ...
authorized the escalation and use of military force in the Vietnam War without a formal declaration of war.
On at least 125 occasions a US president has employed military forces without authorization from Congress.
One of the most significant of these occasions was the
Korean War
{{Infobox military conflict
, conflict = Korean War
, partof = the Cold War and the Korean conflict
, image = Korean War Montage 2.png
, image_size = 300px
, caption = Clockwise from top:{ ...
, a conflict that resulted in over 142,000 American casualties (about 40,000 deaths and over 100,000 injuries).
See also
*
Proxy war
A proxy war is an armed conflict between two states or non-state actors, one or both of which act at the instigation or on behalf of other parties that are not directly involved in the hostilities. In order for a conflict to be considered a p ...
References
{{mil-stub
Wars by type
Warfare by type