In Trump v. Hawaii, 138 S.Ct. 2392 (2018), the U.S. Supreme Court ruled 5-4 that the lowest level of constitutional scrutiny, rational basis review, must be applied to an Establishment Clause challenge to Presidential Proclamation 9645 indefinitely barring entry of nationals from five predominantly Muslim countries. The court determined that apart from any religious hostility allegedly reflected in the president's statements as a candidate and as president, there was persuasive evidence that the facially neutral proclamation had a legitimate grounding in national security concerns in preventing entry of nationals who could not be adequately vetted and in inducing other nations to improve their identity-management and information-sharing practices, and that the proclamation's policy denying certain foreign nationals the privilege of admission reflected the results of a worldwide review process undertaken by multiple Cabinet officials and their agencies. Although five of the seven countries affected are majority Muslim, the proclamation is facially neutral and covers just 8 percent of the world's Muslim population and was limited to countries that were previously designated by Congress or prior administrations as posing national security risks; thus, the proclamation did not support an inference of religious hostility on rational basis review. The court assumed without deciding that the plaintiffs' claims are reviewable, notwithstanding consular nonreviewability. The court rejected the plaintiffs' claim that the proclamation is inconsistent with the Immigration and Nationality Act.