But here the complex nature of the government which they were obliged to establish made it necessary to depart from the theoretical correctness of a general principle. The sovereignty of the States would be entirely inconsistent with a power in the general government to control their whole legislation. As the direct authority of the national legislature was to extend only to certain objects of national concern, or to such as the States were incompetent to provide for, all the political powers of the States, the surrender of which was not involved in the grant of powers to the national head, must remain; and if a general superintendence of State legislation were added to the specific powers to be conferred on the central authority, there would be in reality but one supreme power in all cases in which the general government might see fit to exercise its prerogative. The just and proper sphere of the national government must be the limit of its power over the legislation of the States. In that sphere it must be supreme, as the power of each State within its own sphere must also be supreme. Neither of them should encroach upon the prerogatives of the other; and while it was undoubtedly necessary to arm the national government with some power to defend itself against such encroachments on the part of the States, there could be no real necessity for making this power extend beyond the exigencies of the case. Those exigencies would be determined by the objects that might be committed to the legislation of the central authority; and if a mode could be devised, by which the States could be restrained from interfering with or interrupting the just exercise of that authority, all that was required would be accomplished.[30] But to do this by means of a negative that was to be classed among the legislative powers of the new government, was to commit the subject of a supposed conflict between the rights and powers of the State and the national governments to an unfit arbitration. Such a question is of a judicial nature, and belongs properly to a department that has no direct interest in maintaining or enlarging the prerogatives of the government whose powers are involved in it.