The preamble says in effect that humans have the right to choose their government, that means if we find we are being enslaved we can throw off the shackles, if the throwing off is peaceful, that would be secession, if it is violent, that is revolution.
The war between the states is an example of a non-peaceful secession, even though the confederate states peacefully seceded the Union wouldn't allow it, therefore there was a bloddy conflict.
The Union cannot force the states to stay in the Union of the people don't want to unless they use force. It may work out slightly differently this time around.
BTW, even without a constitution, people have the God given right to choose their government, that includes Americans.
Correct to post 113. bloddy conflict = bloody conflict.
But it doesn't matter.
If you decide to leave and have the power to back it up, the law doesn't mean a whole lot.
What preamble you reading? Perhaps the Declaration of Independence?