If both the President and the Vice President can no longer serve, who becomes President?

In the scenario where both the President and the Vice President are unable to serve, the Speaker of the House becomes the President of the United States. This process is established in the Presidential Succession Act of 1947, which outlines the order of succession.

The rationale behind this decision is rooted in the democratic principles of the U.S. government. The Speaker of the House is an elected member of Congress and represents a portion of the American population, thus maintaining a certain level of democratic legitimacy in the line of succession. Additionally, the Speaker is responsible for leading the House of Representatives, which plays a critical role in legislative processes, making them a fitting choice for assuming the presidency in emergencies.

The other options do not follow this chain of succession. The Secretary of State would come after the Speaker of the House in the line of succession. The Senate Majority Leader and the Chief Justice of the Supreme Court are not part of the established presidential succession framework, which is specifically designed to ensure continuity of governance through elected officials in Congress.