The War Powers Resolution Act was enacted in 1973 to bring under control the ability of the president to involve U.S. Armed Forces in military engagements or wars. According to the Act, the president has to consult and seek approval from the Congress before engaging American forces in foreign hostilities.
According to Grimmett (2010), the War Powers Resolution Act was enacted to prevent future presidents of the United States from engaging the Armed Forces in wars similar to the Vietnam War that resulted in extremely negative effects for the United States. It was further argued that a president would easily abuse his or her constitutional rights as the Commander-in-Chief of the Armed Forces when engaging U.S. Forces in foreign hostilities.
The Act requires the president to seek approval from the Congress before involving U.S. Armed Forces in any military engagement (MacCormick, 2008). An approval from the congress should be sought within sixty days. Despite this legal requirement by the Act, some former presidents of the United States of America such as Richard Nixon vetoed the law on the basis that the Act infringed their constitutional authority as Commander-in-Chief of the Armed Forces.
Other war powers that exist for the executive and legislative branches include the power to initiate military operations in foreign hostilities as well as supporting such operations, the power to decide collectively on military attacks and the power to declare war against foreign hostilities or looming threats. The executives and legislatives also have the power to declare emergency war against foreign attackers. This power is granted by the emergency war power act of 1941.
In addition, the Congress also has the power to extend period of engagement or terminate any military engagement of the U.S. Armed Forces into hostilities. For example, section 5(c) empowers the congress to order the president to withdraw U.S. Forces from foreign military engagements.
In my opinion, such power struggles would be more common in foreign policy areas than in domestic policy areas because various political leaders would express divergent views pertaining to foreign military engagements. Whereas some leaders would view foreign military engagement as a waste of national resources, other leaders would support the policy and thus lead to a conflict of interests amongst the leaders. Consequently, power struggles would emerge.