In military/security studies and international relations, police action is a military action undertaken without a formal declaration of war. Today the term counter-insurgency is more used. Since World War II, formal declarations of war have been rare, especially actions conducted by developed nations in connection with the Cold War. Rather, nations involved in military conflict (especially the major-power nations) sometimes describe the conflict by fighting the war under the auspices of a "police action" to show that it is a limited military operation different from total war. The earliest appearance of the phrase was in 1883, referring to attempts by Netherlands forces and English forces to liberate the 28-man crew of the SS Nisero, who were held hostage. The Dutch term politionele acties (police actions) was used for this. The Merriam-Webster's Collegiate Dictionary: Eleventh Edition called it in its 1933 issue; a localized military action undertaken without formal declaration of war by regular armed forces against persons (as guerrillas or aggressors) held to be violators of international peace and order. It was also used to imply a formal claim of sovereignty by colonial powers, such as in the military actions of the Netherlands, United Kingdom, and other allies during the Indonesian National Revolution (1945–1949) and the Malayan Emergency (1948–1960). Examples of "police actions" The various Banana Wars, from April 21, 1898 to August 1, 1934, were called police actions by the US government. The two major Dutch military offensives, of July 1947 and December 1948, during the Indonesian National Revolution were referred to by the Dutch government as the first and second "police actions". The 1948 action, by India, against Hyderabad State, code named Operation Polo, was referred to as a police action by the government. In the early days of the Korean War, President Harry S. Truman referred to the United States response to the North Korean invasion of South Korea as a "police action" under the aegis of the United Nations. Shortly after the secession of Biafra in 1967, the Nigerian military government launched a "police action" to retake the secessionist territory beginning the Nigerian civil war. The Vietnam War and the Kargil War were undeclared wars and hence are sometimes described as police actions. The Soviet–Afghan War was an undeclared war and hence also could be described as a police action, especially since the initial troop deployments into Afghanistan were at the request of the Afghan government.