As the Trump Administration explores diplomatic and military responses to the provocative nuclear testing by the North Korean government, the executive branch’s authority to unilaterally commit U.S. armed forces to combat operations once again faces scrutiny. While the power to declare war is an enumerated one, exclusively reserved for the legislative branch, the executive branch has significantly expanded its war making authority since the end of World War II. Legislation introduced by Congress – such as the 2001 Authorization of Military Force – often blurs the line between Congress’ role in authorizing force and the president’s duty to act decisively as commander-in-chief. Congress has not effectively challenged modern presidential assertations of power, effectively ceding much of its war making responsibility to the president. While the War Powers Resolution of 1973 remains the strongest legislation that Congress has passed to reassert its relinquished power, the law has always been inherently weak and will require clarification to be effective in the 21st century.When structuring the Constitution, the founders were clearly wary of the president waging war against the wishes of the legislature. Centuries of European monarch rule left them keenly aware of the danger of entrusting any single individual to commit a nation to war, and this led them to delegate that authority to the legislative branch. As the necessary response time to react t0 foreign threats – originally measured in weeks and months – was reduced to mere minutes, as the Soviet Union began perfecting its nuclear tipped ballistic missile program, the founders’ mandate of congressional approval became unrealistic. Congress was forced to surrender some of its power to the president to allow for him to respond to threats in a moment’s notice. Importantly, they conceded the power for the president to unilaterally launch nuclear weapons to deter Soviet attacks; a power that remains unchecked by any other branch of government or cabinet member.Attempts to reel back power only came after years of conflict in Vietnam without a formal declaration of war. The Gulf of Tonkin Resolution, passed in 1962, gave President Johnson the authority to commit U.S. armed forces to “do whatever necessary in order to assist any member or protocol state of the Southeast Asia Collective Defense Treaty.” This broad authorization acted as a blank check written to the president to fight whatever threats in the region he deemed necessary. Predictably, abuse ensued after years of this unchecked authority. The release of the Pentagon Papers in 1971 revealed that Congress had not been adequately briefed on the full scale of military operations in Indochina, including extensive bombing campaigns in Cambodia and Laos. This leak exposed evidence that two successive presidents – in different political parties – greatly expanded their military authority without the consultation of Congress. As a bipartisan coalition of congressional leaders felt betrayed by Presidents Johnson and Nixon, they started to fear their check on the executive branch was eroding. In response, Congress passed the War Powers Resolution over President Nixon’s veto in 1973.By exercising the “necessary and proper clause” found in Article I of the constitution, Congress limited the president’s ability to commit armed forces to conflict. Congress required the president to send a written report of any large-scale armed service deployment to them within 48 hours. Limits were then set on how the long troops can remain deployed without a formal declaration of war or an authorization of military force. Without congressional approval, troops can only remain deployed for 60 days, and when that time expires, the president has just 30 additional days (a maximum deployment of 90 days) to withdraw all remaining troops.While the law’s language is explicit in its restrictions, the War Powers Resolution has proven to be all but unenforceable in practice. Serious structural questions pertaining to the law’s constitutionality remain unlitigated, and glaring weaknesses – like its failure to specifically indicate the consequences a president faces if they simply choose to ignore it – give Congress a weak hand when trying to enforce the law.Ironically, the Nixon Administration’s legal arguments in 1973 have held up well and continue to cast doubt on the law’s constitutionality. Section 5 of the War Powers Act – the section requiring the automatic withdrawal of troops in 30 additional days – stands on shaky legal ground; many legal scholars consider it unconstitutional. When vetoing the bill, President Nixon argued that Congress did not have the authority to force a president to withdraw troops through inaction. His interpretation was that Congress needed to act legislatively if they wanted to force withdrawal, meaning the automatic withdrawal mandated after 60 days is unconstitutional. This argument appears to be internally valid. Courts have consistently ruled that the president acts with the implied support of Congress, so as long Congress does not act to force withdrawal, the courts remain unlikely to intervene. Many argue that the War Powers Resolution might also violate the separation of powers doctrine in the constitution, and executive branch officials have long held the view that this makes the law unenforceable. When the president notifies Congress of military deployments, officials are vigilant to use the phrase “consistent with the War Powers Resolution”, as opposed to “pursuant to the War Powers Resolution”, in their reports to Congress to emphasize their interpretation that the law is unconstitutional.Another weakness is the triggering language of the law, which is inflexibly written and insufficiently adaptive to new forms of warfare. The definitions of “armed forces”, “territories”, and “hostilities” are broadly defined, leaving presidents too much room for interpretation.According to the War Powers Resolution, the “introduction of armed forces equipped for combat into the territory, airspace, or waters of a foreign nation” acts as a trigger for the law’s implementation. However, the legal definition for “armed forces” is narrowly written and has not aged well into the age of artificial intelligence and drone warfare. The law explicitly defines “armed forces” as the deployment of military personal, often referred to as “boots on the ground”. The second half of the triggering phrase, “the territory, airspace, or waters of a foreign nation”, fails to account for modern advances in warfare, such as cyber-attacks, that can extend far beyond a country’s physical borders.In 2011, President Obama’s use of drone warfare in the NATO military intervention to overthrow Libyan dictator Muammar Gaddafi exemplifies the law’s modern feasibility and the liberal interpretations of the triggering phrases. During the intervention, the Obama Administration determined that the use of armed, manually-piloted Air Force drones did not meet the definition of armed forces, as defined by the War Powers Resolution, and, consequently, did not trigger his reporting requirements. Because there were no U.S. soldiers directly involved in combat, the Obama Administration also argued the drone strikes did not constitute “hostilities”, a definition that would have triggered the law. While President Obama received bipartisan criticism for his interpretation, he proceeded unabated with the campaign, without a serious congressional challenge.While this argument is certainly not unassailable, it is unlikely to face a serious legislative or judicial challenge in the future, unless key sections of the law are further refined to apply to emerging forms of warfare. These static definitions have become increasingly antiquated and will continue to do so as technology advances. As currently interpreted, there is no precedent that implies that War Powers Resolution regulates remote drone strikes, offensive cyber-attacks, the use of autonomous weapons, nanotechnology attacks, or the seemingly unavoidable introduction of robots built for warfare in place of “boots on the ground”. This presents a serious problem for congressional oversight. Drones equipped with artificial intelligence will inevitably become more lethal and increasingly miniaturized – eventually to the microscopic level – leading to their use making up a far larger proportion of military operations.If Congress wishes to reassert its war declaration powers, the War Powers Resolution will need to be reformed or entirely re-written. Despite the military budget being at an all-time high and U.S. armed forces’ involvement in military campaigns across the globe, Congress has not formally declared war since 1942.If Congress can unite to reclaim its enumerated authority, an unlikely development in a partisan and deeply divided Congress, negotiations over reforming the 2001 Authorization of Military Force could provide the leverage needed to force concessions from the Trump Administration. This could lead to the eventual reform of the War Powers Resolution. If Congress chooses not to act to restrain the executive branch, their inaction will slowly cede complete control of the military to the president. However, Congress will not be acting out of character; they will simply be following the status quo they themselves set eight decades ago.