The domestic and geopolitical disaster of the Vietnam War, and the process that took the United States into such a large-scale and protracted conflict, led Congress to reinforce its checks on executive war powers. The resulting War Powers Resolution (WPR) sought to inject Congress back into the decision-making process, yet no President has ever acknowledged its constitutionality. The initial debates around the WPR revealed four major lines of argument on the balance of war powers; three of those continued to be made over the next 40 years, as Presidents from both political parties deployed U.S. forces abroad, often without Congressional authorization. This study analyzed the prevalence and distribution of those lines of argument in the U.S. Senate over the Republican Administration of President George W. Bush and the Democratic Administration of President Barack Obama. Both administrations were involved in multiple deployments of U.S. forces abroad, and experienced opposition from both parties. The study found that Democrats displayed consistency across both administrations, indicating a preference for institutional loyalty in supporting compliance with the WPR, whereas Republicans tended to support the status quo. In addition, the study found that Senators from both parties acknowledged the rapidly changing nature of warfare as new technologies mostly remove U.S. armed forces from harm's way even as they conduct lethal strikes. What effect this has on Congress's ability and willingness to further check executive war powers remains to be seen, but it is clear that the debate is far from over. / Master of Arts