No. It simply wasn’t. The American Revolution was just that, a Revolution. It was a rebellion in an attempt to set up an entirely new form of government based on entirely different principles. It was successful.
The rebellion of 1861 wasn’t about a new form of government. The only real difference between the stated purpose of the CSA rebels and the government they attempted to leave was the protection of and the expansion of the institution of slavery. In their effort to protect and extend the institution of slavery, they lost.
The American Revolution was not secession, it was rebellion and revolution to set up a new form of government. The slaveholder’s rebellion of 1861 wasn’t about a radical change in government or society- it was about the protection of and expansion of slavery. They didn’t try to set up a new form of government but basically copied the old form amongst themselves as slave holding states. They said so themselves. If you disagree, your argument is with the confederates. South Carolina, Mississippi, and other states told us exactly why they did what they did. Confederate political and military leaders told us exactly why they did what they did.
Why do you refuse to believe them?
The Cambridge English Dictionary defines secession as the act of becoming independent and no longer part of a country, area, organization, etc. In 1783, the 13 American colonies became independent and no longer part of the United Kingdom which is secession.