Final answer:
Popular sovereignty is the principle where government is based on the consent of the people, as introduced in the U.S. Constitution's preamble. It has expanded with amendments that extend voting rights and through the idea of the Constitution as a living document. This democratic principle and federalism both have evolved to reflect societal changes and maintain a balance of authority.
Step-by-step explanation:
Popular sovereignty is a foundational principle that represents the idea that the legitimacy of a government is created through the will and consent of the people it governs. This concept is applied in the U.S. Constitution, specifically in the preamble, which begins with 'We the People,' indicating that the authority of the government derives from the citizens.
Over the years, the principle of popular sovereignty has expanded through various means such as constitutional amendments, judicial interpretations, and changes in societal values. For instance, the extension of suffrage rights through the 15th, 19th, and 26th Amendments reflects the adaptation of popular sovereignty to include a broader range of citizens.
Moreover, the idea of the Constitution as a living document implies that it is adaptable to the changing needs and beliefs of society, allowing the principles, including popular sovereignty, to evolve over time. Federalism, as another constitutional principle, has also changed, delineating the distribution, sharing, and limitation of power between the national and state governments, thus maintaining a balance reflective of the people's will.