Sovereignty is the claim to final authority within a territory — the right to make ultimate decisions, answer to no higher power, and exclude others from intervening. It is not a fact but a claim, and the most revealing cases are the ones where two sovereignty claims collide and neither can yield without ceasing to be sovereign.
Taiwan has a government, an army, a currency, a passport, and elections. It also lacks recognition from most of the world’s states, including its largest neighbor, which claims sovereignty over it. The question of whether Taiwan is a sovereign state has no clean answer — because sovereignty is not a condition you either have or lack. It is a claim that others must recognize, and recognition can be withheld. That gap between the claim and its recognition is where sovereignty lives.