Here is a brief but you already know---
http://en.wikipedia.org/wiki/Texas_v._White
Texas v. White, 74 U.S. 700 (1869) was a significant case argued before the United States Supreme Court in 1869. The Court held in a 5–3 decision that Texas had remained a state of the United States ever since it first joined the Union, despite its joining the Confederate States of America and its being under military rule at the time of the decision in the case. It further held that the Constitution did not permit states to secede from the United States, and that the ordinances of secession, and all the acts of the legislatures within seceding states intended to give effect to such ordinances, were "absolutely null".
Just a few points to make.
1.No Confederate state remained a state in the union during the "rebellion." If that was the case they should not have had to be re-admitted.
2. Texas was under military rule, how fair can the trial be?
3. There is nothing in the constitution that says a state cannot withdraw from the Union. Lincoln even said as much.
4. The court's opinion was authored by Chief Justice Salmon Chase, himself a former cabinet member under Abraham Lincoln and leading figure in the Union government during the American Civil War.
Any 5th grader can see this is a biased opinion and that the the whole basis of your argument.
GP