Tim — Not for most modern states, although, maybe some micro-states might fit that definition. Also, some states (eg Saudi) encompass many clans but the government is dominated by a single clan.

Then, too, the political leaders of many if not all states tend to share many clan values, such as greater emphasis on things like loyalty and honor (the “guardian syndrome”), than the average citizen of liberal democracies. For a fully developed version of that argument, see Jane Jacobs, “Systems of Survival”. (Synopsis here)