The Civil War was the greatest constitutional crisis in the nation's history. It tested the nation-state relationship and the powers of Congress, the President, and the courts. By ultimately destroying SLAVERY, the conflict removed the most destructive element in the constitutional system and produced promises of equality under law throughout the United States. The addition of the THIRTEENTH AMENDMENT, FOURTEENTH AMENDMENT, and FIFTEENTH AMENDMENT dramatically changed the structure of the federal system in important respects. In the short run these amendments ended slavery and gave state and national CITIZENSHIP to over four million black men, women, and children. They also opened the door for black participation in politics. By the mid-twentieth century the amendments would place a great many individual rights under federal protection.
The was also finally settled the long-debated question of SOVEREIGNTY. When a state and the national government clashed over ultimate authority, the national government would prevail. This primacy did not mean, however, that the states were stripped of power or influence. Both state and national governments involved themselves energetically and successfully in war-making and hence increased both their influence and their stature before the people. State and federal taxation increased along with state and federal expenditures for public projects. The war thus produced an ironic dual legacy: freedom for black Americans and a vital federal system in which states would retain significant, though no longer unique, influence over the amount of freedom these freedmen would exercise.
Because Congress was in recess when the conflict began, the President had to cope with the crisis alone. ABRAHAM LINCOLN answered secessionist rhetoric with a powerful argument that sustained national authority by noting the danger of anarchy in SECESSION and by emphasizing the sovereignty of people, not states. "A majority, held in restraint by constitutional checks, and limitations, and always changing easily, with deliberate changes of popular opinions and sentiments, is the only true sovereign of a free people," Lincoln said. To preserve the constitutional system that embodied this process, Lincoln was willing to lead the Union into war.
Lincoln marshaled northern resources to fight secession. He called for troops, paid $2 million from the treasury, pledged federal credit for $250 million more, and proclaimed a blockade of southern ports. These initiatives raised the constitutional problem of whether the conflict was legitimate at all, for Lincoln had acted without statutory authority and only Congress had power to declare war. In the March 1863 PRIZE CASES, the Supreme Court gave its answer on the disposition of several ships seized by the Union navy after Lincoln's 1861 blockade. The constitutional question was whether the President could blockade the South without a DECLARATION OF WAR by Congress.
Emphasizing the distinction between an international war, which Congress had to declare, and a civil war thrust upon the President and demanding immediate response, the Court defined the war as an insurrection, thus recognizing the President's power to subdue the rebellion without recognizing the Confederacy as an independent nation. The Court also justified Lincoln's action on the basis of the Militia Act of 1795, which allowed the President to call up the federal militia to stop insurrections. Presidents JOHN QUINCY ADAMS, JAMES K. POLK, MILLARD FILLMORE, and FRANKLIN PIERCE had established precedents in exercising this power, and the 1827 case of MARTIN V. MOTT had sustained it.