The government asserts that the lack of a formal declaration of war is not relevant to the existence of a war and unnecessary to invoke the law of war. While a declaration is unnecessary for the existence of an armed conflict according to the international law of war, it may be argued that a formal declaration is necessary to determine what law applies domestically, whether to aliens or citizens. 203 For example, the Alien Enemy Act and the Trading with the Enemy Act (TWEA), 204 both of which regulate the domestic conduct of persons during a war, expressly require a declared war and are not triggered by the authorization to use force.205 The Emergency Detention Act, in effectfrom 1950 to 1971, had similar requirements prior to the invocation of its measures.