USA states have their own: police force, congress, judiciary, laws, taxes, constitutions, and so on. So I'm not sure what you mean by comparing the City of London to USA states - it isn't really meeting your criteria aside from not having a standing military which is also true for some countries/states outside of the USA.
USA states have their own: police force, congress, judiciary, laws, taxes, constitutions, and so on. So I'm not sure what you mean by comparing the City of London to USA states - it isn't really meeting your criteria aside from not having a standing military which is also true for some countries/states outside of the USA.