Abstract The doctrine of the Act of State and State Immunity has its foundation in common law frameworks. It is settled law that there is no cause of action that will make a foreign state liable in the domestic court of another country. In the United States there has been acceptance that certain cases involve “political questions” that are non-justiciable, as they are not a “case or controversy” as required by Article III of the U.S. Constitution. The courts have only intervened either where the federal statutes have applied extraterritorially, such as under the Civil Rights Act 1964 where a U.S. citizen is employed abroad by a company registered in the United States, or under the Alien Tort Claims Act (ATCA) 1789, which protects foreign parties who are designated sufficiently “alien” for the sole purpose of invoking jurisdiction after a civil wrong has been committed against them. There needs to be an evaluation of the U.S. Supreme Court precedents that have asserted judicial oversight in respect of wrongs committed extra-territorially, and their present rationale for retaining the doctrine. This paper also discusses the scope of the Federal State Immunity Act (FSIA) and the Justice Against Sponsors of Terrorism Act (JASTA) that narrow the concept of state immunity when dealing with terrorism by another state or its agents. A comparative analysis with the state immunity doctrine in Canada and the framework for litigation under the merits-based approach by the courts is provided. The common law courts have developed the doctrine of the Act of State and it has become a principle of customary international law. The argument of this paper is that there needs to be a greater focus on the civil injuries that are caused in other jurisdictions that should allow the claimants to litigate in the forum court and for judicial review to be available.