The main purpose of this legislation is to require the Secretary of Homeland Security to promptly start the process of removing individuals from the United States if their visas are revoked for security reasons or related issues. The goal is to enhance national security by ensuring that individuals who pose a threat are dealt with swiftly. Key provisions of the law include a clear mandate that once a visa is revoked due to security concerns, the Secretary of Homeland Security must immediately initiate removal proceedings against the individual.