This is not the only difference between the proposed Indian Federation and other federations. Federalism is described as a weak if not an effete form of Government. There are two weaknesses from which Federation is alleged to suffer. One is rigidity and the other is legalism. That these faults are inherent in Federalism, there can be no dispute. A Federal Constitution cannot but be a written Constitution and a written Constitution must necessarily be a rigid Constitution. A Federal Constitution means division of Sovereignty by no less a sanction than that of the law of the Constitution between the Federal Government and the States, with two necessary consequences (1) that any invasion by the Federal Government in the field assigned to the States and vice versa is a breach of the Constitution and (2) such breach is a justiciable matter to be determined by the Judiciary only. This being the nature of federalism, a federal Constitution have been found in a pronounced form in the Constitution of the United States of America.
