What are the primary principles of the Constitution, and what was their significance in shaping American government?

Generally speaking, there are seven principles of the Constitution. These principles serve as the basic foundation for the US system of government, which is a representative democracy, meaning the people vote for representatives to serve their interests in government. The seven major principles are popular sovereignty, republicanism, separation of powers, checks and balances, limited government, individual rights, and federalism. These principles are interconnected and operate together to shape the way both the federal and state governments work.
Popular sovereignty refers to the idea that the power and authority of the government comes from the will and consent of the people, in this case through elected representatives. Popular sovereignty in the US rests on the principle of republicanism, a system of government in which the people have certain rights (outlined specifically in the Bill of Rights) and vote for officials to represent them in government, thus granting consent to be governed. Individual rights are also important in republican governments—there are certain unalienable rights that the government cannot take away. This system creates a limited government, meaning the government is not all powerful but rather gets its authority from the people and their representatives. This principle also comes from the Enlightenment idea of the Social Contract: in forming a government, people enter into a contract. They give up some rights, such as being able to do whatever they please, in exchange for certain protections and guarantees from the government. If the government fails to uphold these guarantees, the people have the right to dissolve the government.
The final two principles are checks and balances and separation of power. The US has a federal system of government, meaning there are powers that the federal (national) government has, powers the state governments have, and powers that both the federal and state governments share (concurrent powers). For example, only the federal government, through Congress, can declare war. However, both the federal and state governments can tax citizens. Within both the federal and state governments, there is a separation of powers that establishes a system of checks and balances. Separation of powers divides the government into three branches with distinct functions: the legislative branch (Congress) makes laws, the executive branch (the president) enforces laws, and the judicial branch (the Supreme Court and lower courts) ensures laws are constitutional. Each branch has certain checks over the other branches to make sure no one branch has more power than the others. For example, the president can veto laws, but Congress can override vetoes if two-thirds of Congress votes to override the veto.