Final answer:
The president has frequently used military power without direct congressional declarations of war, including actions in Libya, Vietnam, Iraq, and Somalia. These actions have often occurred under the auspices of congressional resolutions, UN mandates, or other forms of authorization that have empowered the executive branch unilaterally.
Step-by-step explanation:
Presidential Use of Military Force-
The president of the United States has utilized singular military power to engage in conflict on several occasions. One event where this power was used is the enforcement of a no-fly zone over Libya in 2011, which involved U.S. jets executing kinetic strikes. Furthermore, without formal declarations of war, presidents have commanded U.S. forces in conflicts such as the Vietnam War and the invasion of Iraq in 2003. The expansion of presidential war powers was exemplified during the Mexican-American War in 1846 when President James K. Polk deployed troops to a contested border area, which led to the outbreak of war. The use of force has sometimes met with challenging outcomes, as seen in the battle of Mogadishu in Somalia, where an operation to capture a warlord led to significant U.S. military casualties and a subsequent withdrawal.
Actions like these are predefined by the War Powers Resolution of 1973, which requires the president to notify Congress within 48 hours of committing armed forces to military action and forbids armed forces from remaining for more than 60 days, with a further 30-day withdrawal period, without an Authorization for Use of Military Force (AUMF) from Congress or a declaration of war. Despite the resolution, the use of military force has been a tool for presidents to act upon their foreign policy objectives, often without explicit congressional approval.