Democracies run on rights, votes and majorities. But what they actually involve are interests and opinions. These influence each other and both are important, on a personal level. But states – the vehicles for democratic systems – actually rely not on interests or opinions, but on identity. Interests and opinions can change, but identity cannot in the same way, otherwise states would dissolves regularly, like governments do. They do not, and no one seriously contends that we should all be voting ourselves in and out of states on a regular basis. (How? Chicken and egg.)
Any such idea, as regularly floated about the EU, is grounds for dispute, confusion and suspicion.
Our identities, which all have multiple layers, are more permanent than opinions, and supposedly less contrived than economic interests. But we all think about different kinds of identity in different ways. Some identities are suitable bases for state formation, and some are not. Sexuality is not, ethnicity can be, religious belief has always failed to measure up to the task.