Presidential systems are known to be ineffective. One only has to look at other countries that have the same system to realize that (take a look at central and South america).
It makes changes in law slow as 3 branches are competing with each other for power. This is unacceptable in a fast paced life of the 21 century.
For those who say the constitution can be amended, it's true but it is very SLOW. The document was written to benefit white Anglo Saxon males who owned property at it's inception. If you didn't check any of those boxes, you are out of luck. Changes did occur but only after a civil war, WW2, civil rights movement, etc.
It wasn't precise in its Bill of rights. It had very vague notions about how weapons were to be owned and for what purpose. It also didn't clearly spell out that religion should not have one foothold in government. That is clearly made evident when you see a bible in a courthouse.
I could go on and on. What we need is a parliamentary system with proportional voting, STV (used in Ireland), a new constitution for the modern era, and complete removal of business and religion from political power.
The US constitution was formed by wealthy men who where tired of being taxed by a government halfway across the ocean so they decided to create a paper that once independence was granted would allow the rich the power they needed to protect their interests. Whilst it is a wise idea the paper was written by the wealthy to protect themselves and their money.
It is so old and full of history that the United States can't afford to get rid of it no matter what anyone says. It is so cool to be able to see the thought that was put into the new contry way back so I think we should keep it.
Technology and culture may change, but Human nature never does. And the U.S. Constitution expertly takes Human nature into account in its design of government. Changes in culture and technology are already reflected in the U.S. Code, passed by Congress, etc. Also, the U.S. Constitution was designed to be amended, and it already has been 27 times. It may be harder today to amend it because we have 50 States now instead of 13, but that doesn't mean that it doesn't work; it just means that there are more people involved. (And this is where the federalism of the 50 States comes in. States can be as blue, red, or purple as they wish, no matter the general direction of the federal government!)
In other words, our constitution is a binding that can be amended as time progresses. It is the base of our country. It is mostly flexible, and it is so well written the first parts have not been changed since the time the constitution was applied. We the people. The constitution supports the US as a whole, as one (1).
The constitution was written for everyone denoted by the first phrase:
We the people
This clearly represents the U.S. as a whole, not as a cluster of people. We are cells, and honestly, cells are based solely on chemical reactions. This may sound humbling, but we perceive illusions and process our memories and the things around us. That is it.
We are simple, and simplicity fits nice together. We are linked as one.
Those who claim the constitution is obsolete, have not read the 5000 year leap, the Constitution or the Federalist papers. In other words, they no very little about the constitution except to say it is 400 years old. (Quoting Democrat congressman, Shela Jackson Lee) :( If it is obsolete, why do we still have an oath of office. Those who think the Constitution is obsolete don't understand the oath any way.
The US Constitution is not obsolete. Neither originalism nor living constitutionalism as theories are capable of making such an assertion that is to be taken in any serious regard.
First, we have Article V in the Constitution. True, it can be said, it is rather difficult to pass amendments because of the high threshold of congresspersons and/or state legislatures needed to ratify. However, it has been done, and with great zeal and success.
The 14th Amendment is a clear-cut example; there are other examples too. Essentially, the that particular amendment further empowered Article III--the judicial power vested in the US Supreme Court. The Supreme Court has taken the lead in, I suppose, "updating" the Constitution for the United States, for better or worse--an entirely different argument.
We do have orignalism generally desiring a plain, 18th century reading of the constitution. The argument that it could possibly be obsolete is readily dispensable ipso facto.