"[4] The majority view is that a preventive war undertaken without the approval of the United Nations is illegal under the modern framework of international law.
[9] The UN High-level Panel on Threats, Challenges and Change stopped short of rejecting the concept outright but suggested that there is no right to preventive war.
If there are good grounds for initiating preventive war, the matter should be put to the UN Security Council, which can authorize such action,[10] given that one of the Council's main functions under Chapter VII of the UN Charter ("Action with Respect to Threats to the Peace, Breaches of the Peace, and Acts of Aggression") is to enforce the obligation of member states under Article 4, Paragraph 2 to "refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state .
[11] The Charter's drafters assumed that the Council might need to employ preventive force to forestall aggression such as initiated by Nazi Germany in the 1930s.
[12] The Axis powers in World War II routinely invaded neutral countries on grounds of prevention and began the invasion of Poland in 1939 by claiming the Poles had attacked a border outpost first.
In the summer of 1941, Germany invaded the Soviet Union, inaugurating the bloody and brutal land war by claiming that a Judeo-Bolshevik conspiracy threatened the Reich.
Iranian Shah Rezā Shāh appealed to US President Franklin Roosevelt for help but was rebuffed on the grounds that "movements of conquest by Germany will continue and will extend beyond Europe to Asia, Africa, and even to the Americas, unless they are stopped by military force.
For example, in May 1940, the base of the US Pacific Fleet that was stationed on the West Coast was forwarded to an "advanced" position at Pearl Harbor in Honolulu, Hawaii.
Supporters of the war have argued it to be justified, as Iraq both harbored Islamic terrorist groups sharing a common hatred of the United States and was suspected to be developing weapons of mass destruction (WMD).
In support of an attack on Iraq, US President George W. Bush stated in an address to the UN General Assembly on September 12, 2002 that the Iraqi "regime is a grave and gathering danger.
[37] In Congress, preventive warriors counted Deputy Secretary of Defense Paul Nitze,[38] expert on the Soviet Union Charles E. Bohlen of the State Department, Senators John L. McClellan, Paul H. Douglas, Eugene D. Millikin, Brien McMahon (Chairman of the Atomic Energy Committee), William Knowland and Congressman Henry M. Jackson.
[39][40][41][42][43] John von Neumann of the Manhattan Project and later a consultant for the RAND Corporation expressed: "With the Russians it is not a question of whether but of when… If you say why not bomb them tomorrow, I say why not today?
[61][62] However, during several of the East-West confrontations that marked the first decade of the Cold War, well-placed officials in both the Truman and Eisenhower administrations urged their Presidents to launch preventive strikes on the Soviet Union.
[64]In 1953, Eisenhower wrote in a summary memorandum to his Secretary of State, John Foster Dulles: In present circumstances, "we would be forced to consider whether or not out duty to future generations did not require us to initiate war at the most propitious moment we could designate.”[65] In May 1954, the JCS’s Advance Study Group proposed to Eisenhower to consider “deliberately precipitating war with the USSR in the near future,” before Soviet thermonuclear capability became a real menace.