Of course. Vassels, citizens, and serfs all exist at the pleasure of a sovereign.

But other sovereigns exist at the sufferance of other sovereigns.

Meaning that two sovereigns only exist to the extent that there is no reason or ability for one to subsume the other.

At this point, it is potentially reasonable to say that the only true sovereigns on Earth are the nuclear armed nations, as they are the only ones that potentially can absolutely resist the other nuclear sovereigns (through MAD).

If you’re not armed with nuclear weapons, then you only exist at the pleasure of one or more nuclear sovereigns, so you’re merely a vessel.

Ukraine, for instance, is only really able to resist Russia because Russia cannot bring nuclear might to bear, since different nuclear sovereigns would be annoyed. So, practically, Ukraine only now exists at the pleasure of the USA.