The Constitution charges the President with the primary responsibility for protecting the safety of all Americans, and the Constitution gives the President the authority necessary to fulfill this solemn duty. See, e.g., The Prize Cases, 67 U.S. (2 Black) 635, 668 (1863).
It has long been recognized that the President’s constitutional powers include the authority to conduct warrantless surveillance aimed at detecting and preventing armed attacks on the United States. Presidents have repeatedly relied on their inherent power to gather foreign intelligence for reasons both diplomatic and military, and the federal courts have consistently upheld this longstanding practice. See In re Sealed Case, 310 F.3d 717, 742 (Foreign Intel. Surv. Ct. of Rev. 2002).
Grassley, wisely brings up "sleeper cells." And they aren't sleeping.