Although no presidential executive-order authority is mentioned by the Constitution, presidents have issued over 13,000 of these unilateral edicts since 1862, as well as numerous other orders in the form of informal memoranda, which generally receive less publicity but are often even more far-reaching. While some of these orders seem to fall within the president's constitutional authority, others clearly usurp legislative authority or overrule judicial decisions. Many entail highly intrusive interventions into the economy and the lives of private citizens. For details, see "Executive Orders and National Emergencies: How Presidents Have Come to 'Run the Country' by Usurping Legislative Power" by William J. Olson and Alan Woll (available online).

The authority to declare war is specifically assigned to Congress by the U. S. Constitution. Congress has not exercised that authority since 1941, yet a number of military interventions have been executed at the behest of presidents since that time. None of these illegal actions has been provoked by an immediate threat to U. S. territory; moreover, in at least one instance the intervention seems to have been motivated purely by domestic political considerations.