“Global” is as much an attitude as a status; even small cities have international ambitions and philosophies. However, national governments can weaken a city’s influence regardless of its size or importance to the global economy.
https://www.thechicagocouncil.org/blog/global-insight/global-cities-antidote-political-isolationism
“Global cities: antidote to political isolationism.” The Chicago Council on Global Affairs, 29 June 2016.