Final answer:
Sovereign immunity is based on the principle of sovereignty, where a state is exempt from being sued without its consent, maintaining its independence and full authority over its territory.
Step-by-step explanation:
Under the doctrine of sovereign immunity, the foreign sovereign claims to be immune from suit entirely based on its sovereignty. This principle is predicated on the understanding that a state is one of the foundational institutions in the international system which possesses the ability to govern itself independently, the full authority to make war or peace, and to form treaties or alliances with foreign nations. Sovereign immunity makes states immune from lawsuits with out-of-state citizens and foreigners not living within the state borders and is integral to maintaining the territorial and political integrity of a state.