Dec. 3rd, 1867; Message from the President...

“...The judiciary has also given the solemn sanction of its authority to the same view of the case. The judges of the Supreme Court have included the southern States in their circuits, and they are constantly, in banc and elsewhere, exercising jurisdiction which does not belong to them, unless those States are States of the Union.
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“If the southern States are component parts of the Union, the Constitution is the supreme law for them, as it is for all the other States. They are bound to obey it, and so are we. The right of the federal government, which is clear and unquestionable, to enforce the Constitution upon them, implies the correlative obligation on our part to observe its limitations and execute its guarantees. Without the Constitution we are nothing; by, through, and under the Constitution we are what it makes us We may doubt the wisdom of the law, we may not approve of its provisions, but we cannot violate it merely because it seems to confine our powers within limits narrower than we could wish. It is not a question of individual, or class, or sectional interest, much less of party predominance, but of duty--of high and sacred duty--which we are all sworn to perform. If we cannot support the Constitution with the cheerful alacrity of those who love and believe in it, we must give to it at least the fidelity of public servants who act under solemn obligations and commands which they dare not disregard....”
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- President Andrew Johnson, Dec. 3, 1867, Message to the Senate. [Journal of the Senate of the United States of America. A Century of Lawmaking for a New Nation: U.S. Congressional Documents and Debates, 1774-1875]