Generally speaking, some historians, like the late Anthony Smith (both of us being originally a Classicists by academic training), perceived that kinship, the actual or imagined blood link between a group of people, was at the heart of what one might call proto-nationalism. We see this in the Latin word 'gens', which is 'a race or clan, embracing several families united together by a common name and by certain religious rites' according to Lewis and Short.
Gellner, in Thought and Change, talks of bureaucracies being 'the kinship of modern man'. It helps to understand 'bureaucracy' very broadly. It is not merely the civil servants and lower-level representatives of a state's administration one finds when applying for benefits or getting a driver's licence. Large corporations, banks, medium-sized businesses, universities, non-profits -- all of these are run by means of bureaucratic structures that persist beyond the actual life of people who work there. Quite a few workers, especially those who do well out of the globalised economy, network their way through these institutions into retirement. When they network across borders, they tend to remain within the cities that are themselves part of the global network in a way a city like Detroit or Liverpool is not -- San Francisco, London, Tokyo and their subaltern educational sites in Cambridge or Stanford.
In order to show this kinship, scholars should approach it through some kind of social-network analysis. If these global places are slowly becoming some kind of 'hypernational' entity, we should be able to see people not merely moving within a bureaucratic institution, like Barclays Bank, but also across it to Mizuho Financial. And it must be more than a handful of individuals, and these networks should persist over time, having heritability as mentors leave them to their proteges to continue across 'generations'.
I am working with these ideas in an historical context, but I present them here in the hope that some younger scholar might exploit them usefully. I am getting on, and I have enough research projects for the rest of my life.