Presidential power and constitutionalism -- Constitutionalism and executive power -- Dynamic variables in emergency constitutionalism -- Emergencies and constitutional perspectives -- Presidents and constitutionalism -- President lincoln: "popular demand and public necessity" -- President Wilson: "if there should be disloyalty, it will be dealt with with a firm hand of stern repression" -- President Roosevelt : "every possible protection against espionage and against sabotage" -- President Truman : "within the aggregate of his constitutional powers" -- President Bush and constitutionalism -- Torture -- Surveillance -- Detention -- Conclusion : a call for executive constitutionalism -- Presidential power claims and constitutional perspectives -- Executive constitutionalism.