Opposing the Constitution is not treason. The Constitution is a well written document, but it is nevertheless just the current governing document of the USA. It was not the first, and there's nothing inherent to it that makes it the last one either. Waging war against the USA by a citizen is treason. There's nothing treasonous about, for example, arguing against the Constitution in favor of returning to the Articles of Confederation.
Opposing the Constitution is not treason. The Constitution is a well written document, but it is nevertheless just the current governing document of the USA. It was not the first, and there's nothing inherent to it that makes it the last one either. Waging war against the USA by a citizen is treason. There's nothing treasonous about, for example, arguing against the Constitution in favor of returning to the Articles of Confederation.