terms nullification and interposition often have been used indistinguishably. John C. Calhoun indicated that these terms were interchangeable, stating: "This right of interposition, thus solemnly asserted by the State of Virginia, be it called what it may — State-right, veto, nullification, or by any other name — I conceive to be the fundamental principle of our system." During the fight over desegregation of the schools in the south in the 1950s, a number of southern states tried to preserve their segregated schools by passing so-called "Acts of Interposition" that actually would have had the effect of nullification, if they had been valid. These acts were struck down by the courts, whether labelled acts of interposition or nullification. Virginia Resolution Interposition was first suggested in the Virginia Resolution of 1798, written by James Madison, which stated: That this Assembly doth explicitly and peremptorily declare, that it views the powers of the federal government, as resulting from the compact, to which the states are parties; as limited by the plain sense and intention of the instrument constituting the compact; as no further valid that they are authorized by the grants enumerated in that compact; and that in case of a deliberate, palpable, and dangerous exercise of other powers, not granted by the said compact, the states who are parties thereto, have the right, and are in duty bound, to interpose for arresting the progress of the evil, and for maintaining within their respective limits, the authorities, rights and liberties appertaining to them. By this statement, James Madison asserted that the states are "duty bound to interpose" to prevent the harm that would result from a "deliberate, palpable, and dangerous" unconstitutional action by the federal government. Madison did not specify the procedural legal details of how this interposition would be enacted or what result it would have. The Virginia Resolution, unlike the contemporaneous Kentucky Resolutions, did not assert that the states may declare a federal law null and void. The Virginia Resolution thus is sometimes considered to be more tempered than the Kentucky Resolutions, which assert that a state may nullify unconstitutional federal laws. The Kentucky and Virginia Resolutions were not accepted by any of the other states. Seven states formally responded to Kentucky and Virginia by rejecting the resolutions and three other states passed resolutions expressing disapproval. At least six states responded to the Resolutions by taking the position that the constitutionality