If the President can no longer serve, who becomes President?

When the President is unable to fulfill their duties, the Vice President is next in line to assume the presidency. This line of succession is outlined in the Presidential Succession Act and is also supported by the 25th Amendment to the U.S. Constitution. The Vice President's role is to be ready to step in at any moment the President can no longer serve due to reasons such as death, resignation, or incapacitation.

This system is designed to ensure continuity of leadership in the Executive Branch. The other roles mentioned, such as the Speaker of the House, President pro tempore, and Secretary of State, are part of the presidential line of succession but come after the Vice President. The Speaker of the House, for instance, would only assume the presidency if both the President and Vice President were unable to serve at the same time. Thus, it is the Vice President who immediately takes over the responsibilities of the presidency when the need arises.