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

When the President is unable to fulfill their duties due to reasons such as death, resignation, or removal, the Vice President is designated to assume the role of President. This is established by the Presidential Succession Act and the 25th Amendment to the U.S. Constitution, which clearly delineate the order of succession to ensure there's always a functioning leader of the executive branch.

The Vice President stepping in as President provides continuity of government and leadership during unexpected transitions. This framework allows for a swift and orderly transition without leaving a power vacuum.

The other positions listed, such as the Speaker of the House, Secretary of State, and Chief Justice, hold significant responsibilities in government but are not next in line according to the established constitutional succession protocol. Each of these roles has its own importance, but they do not have the constitutional authority to ascend to the presidency unless the Vice President is unable to serve as well or in a specific series of extraordinary circumstances. Thus, the Vice President is the clear and defined successor to the presidency in times of need.