What about Texas v. White? Didn't the Supreme Court rule secession illegal?

This is the case the whole argument hangs on, so it deserves a full answer. Texas v. White (1869) is the one ruling every opponent of Texas independence eventually cites. It is also a single 5 to 3 opinion, written about a bond dispute, by a judge who should never have heard it, resting on a part of the Constitution that grants no power, and conceding in its own text that a state can in fact leave. Take it apart piece by piece and there is nothing left holding the door shut.

The case was about bonds, not secession

Almost no one who cites Texas v. White will tell you what it was actually about. In 1851 Texas received $5 million in U.S. bonds under the Compromise of 1850. During the war the Confederate state government sold some of them. After the war, the Reconstruction government of Texas sued to recover them. The only question the Court had to decide was whether Texas had standing to sue, which turned on whether Texas still counted as a "state" for the Court's jurisdiction. Bonds, standing, jurisdiction. To resolve that, Chief Justice Chase wrote an entire theory of the union into a fight over who owned $135,000 in bearer bonds.

The "indestructible Union" line was never the holding

A court's holding is the narrowest reasoning it needs to settle the dispute in front of it, and only the holding binds future courts. Everything past that is dictum. It can be eloquent and it can be quoted for a century and a half, and it is still not binding law. Chase's "indestructible Union, composed of indestructible States" was not necessary to decide who owned the bonds. It was dictum. And the one piece of the case that was a true holding, the bond rule, was overruled sixteen years later in Morgan v. United States (1885). The rule the opinion existed to deliver did not survive. The slogan everyone repeats did, only because the question has never been squarely put to the Court again since 1869. It has been quoted in passing. It has never been held.

The judge who wrote it had a personal stake in the outcome

Here is the argument the talking point never sees coming. Salmon P. Chase did not come to this case as a neutral referee. Before he was Chief Justice he was Abraham Lincoln's Secretary of the Treasury, from 1861 to 1864, and in that job he personally built the financial machine that paid for the war. He oversaw the war bonds. He launched the greenbacks. He stood up the national banking system. Every dollar of it rested on one premise: that the union was permanent and the war to preserve it was lawful. If a state could lawfully leave, that premise cracked, and the legal foundation under an enormous war debt cracked with it. A judge ruling on the legality of the very system he created, with that much riding on the answer, is not a neutral arbiter. By any standard we would apply today, his impartiality could reasonably be questioned. He was, in effect, a party to the case wearing the robe.

It was not unanimous, and the dissent was never answered

Justice Robert C. Grier dissented "on all points raised and decided." That is not a quibble at the margins. That is a sitting justice rejecting the entire ruling. Grier did not dissent out of any sympathy for the Confederacy. He dissented because he would not call a military occupation a state. In 1869 Texas had no senators, no members in the House, and had cast no votes in the last presidential election. It was run as a military district. Grier wrote that the matter should be "decided as a political fact, not as a legal fiction," and he caught the contradiction at the center of the case: Texas was treated as a state for the purpose of suing, but not a state for the purpose of self-government. It could not, he wrote, "like the chameleon, assume the color of the object to which she adheres." He closed with the line its defenders never quote: "neither my reason nor my conscience can give assent to it." He was outvoted. He was never refuted.

The only textual hook was the Preamble, and the Preamble grants no power

Chase had no clause to point to, so he hung his "perpetual union" on the Preamble's promise of "a more perfect Union." That is the entire textual foundation of the ruling. And it does not hold weight, because the Supreme Court itself later said so. In Jacobson v. Massachusetts (1905), the Court held that the Preamble "has never been regarded as the source of any substantive power conferred on the Government of the United States or on any of its Departments." If the Preamble cannot grant the government a power, it cannot impose on a state an obligation to stay forever. The principle cuts both ways. The one part of the Constitution Chase leaned on is the one part the Court has ruled carries no power at all.

The Framers deliberately deleted the word he needed

There is a deeper problem with "perpetual union." The Articles of Confederation, the document the Constitution replaced, called the union "perpetual" and used the word freely. The Constitution never uses it once. The men who wrote it had the word in front of them, in the very document they were rewriting, and they left it out. In law, a deliberate deletion means something. They chose "a more perfect Union," which describes how well the union is built, not how long it must last. You cannot make "forever" more forever. Chase took a word the Framers had removed and read it back into the text by implication. That is not interpretation.

Three states reserved the right to leave, and Congress accepted it

When the Constitution was ratified, three states said in writing that they kept the right to take their delegated powers back. Virginia, ratifying on June 26, 1788, declared that the powers granted "may be resumed" by the people "whensoever the same shall be perverted to their injury or oppression." New York, on July 26, 1788, reserved that the powers of government "may be reassumed by the people, whensoever it shall become necessary to their happiness." Rhode Island said the same when it ratified in 1790. Congress seated all three without objection, which made that reservation part of the bargain. Under the Equal Footing Doctrine, every state enters the union with the same rights as the original states. The Supreme Court put it plainly in Coyle v. Smith (1911): this is a union of states "equal in power, dignity and authority." You cannot have an original thirteen with an escape clause and the rest locked in. The reservation belongs to Texas too.

Its own author admits a state can leave

For all its sweep, the opinion defeats itself in a single sentence. Chase wrote that there was "no place for reconsideration or revocation, except through revolution or through consent of the States." Read it again. The case used to prove Texas can never leave concedes two lawful exits, one of them being the simple consent of the states. The cage he built has a door, and he drew it himself.

The world's high courts have ruled the opposite way since

While American politicians froze the question in 1869, courts elsewhere kept reasoning. In 2010 the International Court of Justice held that "general international law contains no applicable prohibition of declarations of independence," and that the principle of territorial integrity "is confined to the sphere of relations between States." It does not lock a people inside a state. The Supreme Court of Canada, in its 1998 Quebec decision, held that a clear majority on a clear question creates a binding duty on the rest of the country to negotiate the separation in good faith. Notably, the United States argued for the right of declaration in the Kosovo proceeding and recognized Kosovo the next day. Washington's own stated position abroad contradicts the position it clings to at home.

A war is not a constitutional amendment

The last fallback is always some version of "the Civil War settled it." A war settles who had the stronger army. It does not amend the Constitution. If conquest could settle a question of right, then every question of right is decided by whoever wins the fight, a principle no free people accepts. And it is worth being precise: what is on the table now has nothing to do with 1861. The secession of 1861 was bound up with slavery and was carried out by conventions, not by a vote of the people. Texas independence is the opposite. It is the consent of the governed, decided by a free and fair vote of every eligible Texan of every background. One was a war to hold human beings in bondage. The other is a peaceful ballot to secure human freedom. Treating them as the same thing is either a mistake or a smear.

This was never a question for the courts

Strip everything else away and you reach the simplest point. Whether a people may govern themselves is a political question, not a judicial one. It belongs to the people of Texas, exercised through their own institutions, under Article 1, Section 2 of the Texas Constitution, which reserves to them at all times "the inalienable right to alter, reform or abolish their government." That sentence has no footnote that says "unless a federal court disagrees."

The bottom line

Texas v. White is one divided opinion, written about bonds, by a judge with a personal stake, on a clause that grants no power, using a word the Framers deleted, over the objection of a dissent no one ever answered, and conceding in its own text that a state can leave by consent. It is not the wall its defenders need it to be. The vote is not blocked by the Constitution. It is blocked by politicians, and that is a problem Texans can solve.