Not that theoretical. Scottish independence is a template for how you'd approach it without military conflict. The issue there being that despite voting for an

Not that theoretical. Scottish independence is a template for how you'd approach it without military conflict. The issue there being that despite voting for an independence party for decades they don't actually seem to want it and their referendum to secede failed, partly because the independence movement turned into a generic left wing political party that wasn't very interested in working out the complicated details.