Is giving up sovereignty of a city not the politic speak way to say that a foreign government will rule it with military might? Seems like a toothless leasing o

Is giving up sovereignty of a city not the politic speak way to say that a foreign government will rule it with military might? Seems like a toothless leasing of brand name if not. Being able to say "a corrupt dictator won't steal your factory if you build it here" and have it believed is half the point, no? Can't do that without military presence.