Declarations of war have never been a constitutional requirement for military action abroad.
John YooHuman rights advocates, for example, claim that the mistreatment of Iraqi prisoners is of a piece with President Bush's 2002 decision to deny al Qaeda and Taliban fighters the legal status of POWs under the Geneva Conventions.
John YooApplying different standards to al Qaeda does not abandon Geneva, but only recognizes that the U.S. faces a stateless enemy never contemplated by the Conventions.
John YooAl Qaeda is not a nation-state and it has not signed the Geneva Conventions. It shows no desire to obey the laws of war; if anything it directly violates them by disguising themselves as civilians and attacking purely civilian targets to cause massive casualties.
John Yoo