There are a number of issues with Americas constitution which make it, arguably, unfit for the 21st century. The most apparent issue with the constitution is the overall ambiguity that its based upon. Take for example the eighth amendment which forbids the federal government from imposing cruel or unusual punishments on American citizens. However, whats classed as a cruel or unusual punishment? Many have argued that capital punishment can be seen as a cruel punishment, which has led to some states, such as Illinois, abolishing the death penalty altogether. Though, despite eighteen states abolishing the death penalty so far, there has been no move to amend the constitution to include the death penalty as an example of cruel punishment.
Another example of an ambiguous amendment is the first amendment which protects the right to free speech as well as freedom of religion. However, how far this amendment applies has been questioned on numerous occasions. For example, Texas passed a law which prevented flag desecration (burning of the American flag), however the Supreme Court overturned the Texas law due to it violating citizens first amendment right as flag desecration is seen as an expression of belief, which the first amendment protects. This has led to numerous calls for flag desecration being outlawed via a constitutional amendment, however just like the eight amendment this would be incredibly hard to achieve. This is purely due to how difficult it is to amend the American constitution.
The American constitutions amendment process is long and difficult, which is mainly due to it requiring a supermajority. A supermajority is where 2/3rds of both houses of Congress have to agree to the amendment put forward. Even if either house falls short by one vote, the amendment is dropped. This process was made to be hard intentionally by the Founding Fathers. This was because they believed that the constitution shouldnt be constantly changing, and so they created the need for a supermajority to stop the federal government from making rash, in the moment, decisions which they could grow to regret later on. However, it is this founding belief that has made the constitution, arguably, untenable for the 21st century, which can be contributed to Congress explosive growth over the last 200 years. For example, in 1789 there were only 65 Representatives in the House of Representatives, which grew to 435 by 1963 and plateaued due to the House of Representatives being capped in 1911. This is an increase of 370 over a period of 174 years (meaning that there were two new Representatives every year). This continually increased the amount of people who had to work in unison to pass constitutional amendments, and as evidenced by the 1911 Act which capped the size of the House of Representatives, America grew far more than the Founding Fathers had originally intended.
The constitution can also be seen as unfit for the 21st century due to an ever increasing political pace, as well as rapidly changing circumstances which have led to very different outcomes when compared to the British political system. This can mainly be seen with gun control which is protected in America by the second amendment (Right to bear arms) despite the amount of shootings which have occurred in recent times. An example of this would be the Sandy Hook shooting, which occurred on December 14th 2012 at an elementary school in Connecticut. This caused nationwide outrage which in turn caused support for disarmament groups to increase. However, after several months the support fell away and no constitutional amendments were put through, despite pledges and campaigns from Barrack Obama and Joe Biden.
Now, when compared to England, there was a shooting spree in a Dunblane Primary School in 1996. Following national outrage, much alike that caused by Sandy Hook, guns were criminalised by an Act of Parliament, which was significantly easier to do as the UK does not have a written constitution, rather an unwritten one which is drawn from several sources.
However, despite the faults with the American constitution, it must be fit for purpose if it still exists. This is because if it wasnt fit for purpose, and didnt work at all, it would have been scraped by one of the American administrations after its conception. This is mainly aided by the argument that the constitutions ambiguity is what allows it to adapt to changing circumstances as well as its ability to change without formal review. What is meant by this is the fact that the Supreme Court can uphold or repeal earlier decisions made in relation to the constitution, meaning that if the correct decisions were repealed the constitution could be drastically changed.