How does the constitution provide liberty for american citizens?

The original Constitution limits the powers of the federal government. However, because of fears of oppression, the Bill of Rights (the first 10 amendments) was immediately passed, which guarantee protection of citizens, giving them guarantees of freedom such as freedom of speech and assembly, freedom of the press, the right to bear arms, etc. Built into the original Constitution were safeguards against tyranny such as the checks and balances of the three branches of government, the ability to impeach (remove) an official during a term under strictly limited circumstances. After the Civil War, the rights guaranteed to citizens against the federal government were extended to protection from encroachment by state government through additional Amendments.