No, Texas cannot legally secede from the United States unilaterally.
texastribune.org
Key Legal Precedent: Texas v. White (1869)The U.S. Supreme Court ruled in this case (decided 5-3) that states do not have the right to secede on their own. When Texas joined the Union in 1845, it entered an "indissoluble relation" and the Constitution creates an "indestructible Union composed of indestructible States."
constitutioncenter.org
The Court declared all acts of secession (including Texas's 1861 ordinance) "absolutely null" and without legal effect.
Texas (and the other Confederate states) never legally left the Union, even during the Civil War.
The only exceptions noted: secession could theoretically occur through revolution (successful armed separation) or by consent of the other states (e.g., a constitutional amendment or mutual agreement involving Congress and the states).
ballotpedia.org
This ruling has never been overturned and remains binding precedent. Late Supreme Court Justice Antonin Scalia reinforced it in 2006: "If there was any constitutional issue resolved by the Civil War, it is that there is no right to secede."
houstonpublicmedia.org
Common MythsTexas was once an independent republic (1836ā1845): This is true historically, but the annexation agreement did not reserve a special right to secede. Texas has no unique legal privilege over other states.
texastribune.org
The Constitution is silent on secession: True, but the Supreme Court interpreted the overall structure (including the Preamble's "more perfect Union" and other provisions) as prohibiting unilateral exit.
en.wikipedia.org
Texas could divide into up to five states: This is allowed under the 1845 annexation resolution (with Congress's consent), but it is not secession from the Union.
en.wikipedia.org
Practical RealityNo mechanism exists in current U.S. or Texas law for a state to leave peacefully on its own.
Any attempt would face massive legal, economic, and military barriers (federal authority, courts, military bases, currency, debt, trade, etc.).
Secessionist groups like the Texas Nationalist Movement ("Texit") exist and occasionally push symbolic bills or referendums, but none have legal force or succeeded.
texastribune.org
In short, under established constitutional law, Texas is permanently part of the Union unless the rest of the country agrees otherwise or extraordinary (and unlikely) events occur. The question is more political/historical than a viable legal option today.
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