Is a de jure secession necessary?
We could achieve a de facto secession through strict state level enforcement of the 10th amendment.
Of course, the first time a state attempted to thwart federal enforcement agents, there’d be a fight anyway.
FedGov™ is a paper tiger. No time in history has the standing army been SO small compared to the general population, with 50% is deployed overseas.. I know technology has made a soldier of today equal to 10 soldiers of WWI, But it is still impossible to be at two places at the same time.