Earlier quoted context omitted.
I don't understand the argument that it couldn't require a warrant. The argument is simply that the executive branch has a constitutional right to wiretap without a warrant, unless the the constitution forbids it? There is some judicial oversight in the FISA court of course. What's the argument for why congress can legislate that, but not a more typical warrant?
For the same reason Congress can’t require the President to get the approval of the Supreme Court before he vetoes a bill: Our Constitution gives powers to the executive that cannot be usurped or overruled by Congress, notably in this context to conduct the national defense and foreign affairs. The FISA court exists to ensure that the executive is not operating outside his Constitutional authority, not as a gatekeepe…
This is not true. The constitution explicitly reserves the power to declare war or enact treaties to Congress. Neither the military nor federal law enforcement can spend a single dime, or even exist, without Congressional approval. If the budget allocates no money to mass surveillance, no money is available to conduct mass surveillance.