In the United States libertarian application of the principle was originally not too much embarrassed by inherited institutions. In its most dogmatic form the American conception of the Separation of Powers may be summed up in the following propositions: (1) There are three intrinsically distinct functions of government, the legislative, the executive, and the judicial; (2) these distinct functions ought to be exercised respectively by three separately manned departments of government; which, (3) should be constitutionally equal and mutually independent; and finally, (4) a corollary doctrine stated by Locke--the legislature may not delegate its powers.[30] Prior even to Franklin D. Roosevelt this entire colligation of ideas had been impaired by three developments in national governmental practice: first, the growth of Presidential initiative in legislation; secondly, the delegation by Congress of legislative powers to the President; thirdly, the delegation in many instances of like powers to so-called independent agencies or commissions, in which are merged in greater or less measure the three powers of government of Montesquieu's postulate. Under Roosevelt the first two of these developments were brought to a pitch not formerly approximated, except temporarily during World War I. The truth is that the practice of delegated legislation is inevitably and inextricably involved with the whole idea of governmental intervention in the economic field, where the conditions to be regulated are of infinite complexity and are constantly undergoing change. Granted such intervention, it is simply out of the question to demand that Congress should attempt to impose upon the shifting and complex scene the relatively permanent molds of statutory provision, unqualified by a large degree of administrative discretion. One of the major reasons urged for governmental intervention is furnished by the need for gearing the different parts of the industrial process with one another for a planned result. In wartime this need is freely conceded by all; but its need in economic crisis is conceivably even greater, the results sought being more complex. So in the interest both of unity of design and of flexibility of detail, presidential power today takes increasing toll from both ends of the legislative process--both from the formulation of legislation and from its administration. In other words, as a barrier capable of preventing such fusion of presidential and congressional power, the principle of the Separation of Powers does not appear to have retained much of its original effectiveness; for on only one occasion[31] prior to the disallowance, in Youngstown _v._ Sawyer,[32] President Truman's seizure in April 1952 of the steel industry has the Court been constrained to condemn, as in conflict with that principle, a congressional delegation of legislative power. Indeed, its application in the field of foreign relations has been virtually terminated by