“‘The Constitution gives the power to declare war to the Congress, but Congress has not formally declared war since June 1942, even though our nation has been involved in dozens of military actions of one scale or another since that time,’ McCain said on the Senate floor. ‘There is reason for this: The nature of war is changing.’ Kaine said their bill would allow the president to act militarily for up to seven days, but if a conflict exceeds that time allotment, both chambers of Congress would have to vote to continue to use force. “

Source: Senate bill amends War Powers Act | TheHill