Is it in the interests of Britain to leave or remain in the EU? As we saw in the referendum, there are different Britains and they see their interests in different ways. For a lot of everyday blokes the EU affected their sense of identity in ways they disliked, and they were right in thinking that the EU didn't return much to them by way of economic benefits.
Citizens often think of a state's interests in terms of the promotion of ideals such as democracy, a particular way of life, or other values which they endorse or see as part of their historical continuity and identity. In this domain as in others values are not fixed, and so a state's interests are dynamic and in a constant state of negotiation and construction.
In this era of globalization we are witnessing struggles within individual states about what their identity and interests consist in.