One of the great constitutional struggles in the United States depends on our vision of government. In dealing with that question in connection with the issues of federalism, the prevailing modern wisdom since the 1937 term of the Supreme Court is that we should not trouble ourselves unduly with the concerns of excessive concentration of power that troubled James Madison, and should instead cede vast powers to the national government in the regulation of the economy. The current disputes over the role of the President on matters of national security do not raise issues of federalism, but it does raise questions about the concentration of power. On this question, many people who are content to give the federal government vast control over the economy have become rightly uneasy about affording similar deference to the President whose claims of executive power in connection with the National Security Agency (“NSA”) surveillance dispute make it appear as though he has well-nigh exclusive power in dealing with this issue. In some settings, the claim is the more modest one—if incorrect one—that the President has received all the congressional authorization he needs when Congress passed the Authorization for Use of Military Force Act shortly after September 11, 2001. But in other cases it involves the more robust claim that Congress has no ability to restrict the President in these intelligence gathering activities because Article II of the Constitution vests exclusive authority on these matters in the President. It follows on this view that the Foreign Intelligence Surveillance Act (“FISA”), which purports to limit presidential power, is unconstitutional.