I once thought the same as you but have done some research. Another poster sent me this:
Joining the “ Union” was ever and always voluntary, rendering voluntary withdrawal an equally lawful and viable option (regardless of what any self-appointed academic, media, or government “experts”—including Abraham Lincoln himself—may have ever said).
Guess you better add the Supreme Court to that list.
In Texas v. White (74 U.S. 700, 1869), the Supreme Court said:
"The Constitution, in all its provisions, looks to an indestructible Union composed of indestructible States. When, therefore, Texas became one of the United States, she entered into an indissoluble relation. All the obligations of perpetual union, and all the guaranties of republican government in the Union, attached at once to the State. The act which consummated her admission into the Union was something more than a compact; it was the incorporation of a new member into the political body. And it was final. The union between Texas and the other States was as complete, as perpetual, and as indissoluble as the union between the original States. There was no place for reconsideration or revocation, except through revolution or through consent of the States."
http://supreme.justia.com/us/74/700/case.html
So once in, always in.
I like revolutions when they become necessary.
Here's what Madison had to say on the subject of the rights of the States and the authority of the Supreme Court;
However true, therefore, it may be, that the judicial department is, in all questions submitted to it by the forms of the Constitution, to decide in the last resort, this resort must necessarily be deemed the last in relation to the authorities of the other departments of the government; not in relation to the rights of the parties to the constitutional compact, from which the judicial, as well as the other departments, hold their delegated trusts. On any other hypothesis, the delegation of judicial power would annul the authority delegating it; and the concurrence of this department with the others in usurped powers, might subvert forever, and beyond the possible reach of any rightful remedy, the very Constitution which all were instituted to preserve.
James Madison, Report on the Virginia Resolutions
The Supreme Court had no jurisdictional authority to hear Texas v. White. In fact none of the 3 branches of the federal government can operate outside the areas of authority enumerated in the Constituion.
That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed, That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness. Prudence, indeed, will dictate that Governments long established should not be changed for light and transient causes; and accordingly all experience hath shewn, that mankind are more disposed to suffer, while evils are sufferable, than to right themselves by abolishing the forms to which they are accustomed. But when a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, it is their right, it is their duty, to throw off such Government, and to provide new Guards for their future security.
But Texas DOES have the right to give itself 8 extra US Senators by dividing itself into into 5 states.