The United States Constitution provides the foundation for a strong central government with authority to regulate interstate disputes and commerce, enforce citizens' rights and defend from hostile forces. However, much of it is too vague to provide definitive interpretations. It can be amended, but the process is slow. Citizens vote for representatives directly but don't get a direct vote on policies. There is no way to address bipartisanship.
The Constitution is the structure of fundamental political precedents, procedures and principles that the federal government has operated from since its creation in 1789. It delegates certain responsibilities to federal bodies and others to states. The Constitution divides federal powers between three main branches defined by the separation of powers doctrine and provides a system of checks and balances to prevent one branch from overpowering the others.
The original portions of the Constitution, which included the Bill of Rights when ratified, are very specific about certain topics but vague about most others. Because it is vague, the Constitution is a living document, one that can adapt to changes by adding amendments and through judicial interpretation. This can be either a boon or a hindrance. Amendments add clarity to existing constitutional structure or add rights or restrictions. The original Constitution claimed to favor individual liberty but provided no support for women or slaves. In many cases, existing laws were exploited to keep these groups firmly situated. The 13th Amendment, in 1865, abolished slavery; the 14th, in 1870, made slaves citizens, gave black males the right to vote and guaranteed everyone equal protection under the law; and the 19th, in 1920, gave women the right to vote. Adaptability is the Constitution's greatest strength, but change requires great effort and time.