There are many ways in which the USA is culturally distinct from Europe, or the rest of "the West". Perhaps the most well-known point of differentiation is "culture wars".
It is this which divides America down the middle, effectively dividing it into two societies of opposing social beliefs: left-wing "liberals" and right-wing "conservatives". It is for this reason that Presidential elections in the USA often hang on the whim of the "swing states"; those small number of states where the social balance is finely poised between liberals and conservatives.
In this way, America can be described as probably the only continental-sized power whose opposing social ideologies could be conceivably split into two well-defined "states". As a reminder, Korea has been artificially divided by ideology since the Second World War; British India was divided into two states (India and Pakistan) based on religion. So there is plenty of historical precedence.
There is a strong argument, therefore, that America could do itself (and the world) a favour by resolving the "culture wars" issue by simply dividing into two English-speaking, socially-opposite, nation-states. On the one hand, the "liberal" majority areas of the North-east, Great Lakes region, and the West Coast; and the "conservative" majority areas everywhere else between. As as aside, this would be a far more efficient and peaceable division than that between India and Pakistan, as everyone in America knows where the "red" and "blue" states already are. The small number of "swing states" could then be decided by arbitration.
This is a tongue-in-cheek solution, but there is a very serious point here: "culture wars" are what makes America unique in the civilised world. No other country of such power and size is as perpetually divided as America is over social issues (Belgium would be the nearest European comparison, but its issues are linguistic, not social. Belgium was without an effective government for over a year for this reason, but the outside world didn't even notice).
Gun control is just one of them, now brought back into hard focus after another school shooting. The reasons that gun-owning Americans give for justifying their ownership tend be one (or a number) of the following:
1) to defend their property
2) for self-defence
3) to defend against the government
Let's look at those reasons from an objective point of view.
1) "Defending property". Like any other civilised state, America has a fully-functioning (and armed) police force. So there is no rational reason for a private citizen to not trust the efficiency of their armed police force in dealing with property crime. The only alternative reason for gun ownership is to "discourage" property theft by the threat of ultimate force, supported by law. However, it is unclear what preventative effect (if any) gun ownership has on frequency of property crimes; therefore any fear that gun-owners have of being victims of property crime if they didn't have a gun is more an indication of their lack of trust in the police force, and a lack of trust in society in general. It would be useful to know how many burglars are shot in the home opposed the the number of burglaries committed. I suspect the ratio is minute enough to not discourage burglary: therefore the rationale for private gun ownership is flawed.
2) "Self-defence". As with the point above, the reason for using "ultimate force", this time in a life-threatening situation, is due to a lack of trust in society, and a fear of guns in the hands of criminals. This is obvious: if a criminal wants to perpetrate a crime and thinks the victim may be armed, he will use a gun if possible. Again, it is unclear what preventative effect an armed victim has on the intent of the criminal. Most muggings and assaults take place on the street; as the average gun-owning citizen keeps their gun at home, then it renders the point of the weapon futile once they step out the door. Alternatively, they could turn suburban America into a modern "Wild West" movie, but this is what happens in most gang-infiltrated areas anyway. Therefore, the rationale is lost in either case.
3) "Defending against the government". This is the most frightening rationale of the three mentioned, because is infers that the USA is not a fully-functional nation-state. Private citizens carrying guns because they are defending themselves against the government is a situation most commonly associated with civil war. Alternatively, those people believing this are likely suffering from some form of delusional mental disorder.
Talking of "mental disorders", the USA has some of the highest usage rates of "Prozac" and associated drugs in the world. I recently watched a documentary-film called "I Am Fish-head". The film discussed the link between psychopathy (having gained an intellectual interest in understanding and spreading its awareness), lack of empathy, and the rise of emotionally-stabilising drugs like "Prozac".
Psychopathy is a psychological condition I have discussed before, and don't wish to go into the details:suffice to say it is a syndrome that affects somewhere between 1 and 5 per cent of the population, depending on how broadly you measure it. In America, that means there are at least 2.5 million psychopaths in the overall population. It is a condition that has a biological aspect to it, but is generally brought about through environmental factors in childhood. Psychopathy is (generally) a cluster of personality traits: narcissism, lack of morality, deviousness, lack of empathy/emotional emptiness.
The documentary speculated on the link between the emotion-stabilizing effect of "Prozac" and the lack of empathy in psychopaths: does the over-dependence on "Prozac" in America (pushed by pharmaceutical companies onto the medical profession) create an environment that makes psychopathy more likely in the population? It's an intriguing theory.
And in a country where so many people have access to guns, do you really want them to become emotionally empty and potentially devoid of empathy?
It's hardly any wonder that America is such a socially-dysfunctional world power. The right to life; the right to bear arms; Creationism; the "evil" of homosexuality; climate change-denial; the "War On Drugs", the list of issues in the "culture wars" is long and irreconcilable.
To outsiders in other parts of the civilised world, America will always be the great enigma: effectively two opposing societies cleft together; bound together by a shared love of the concept of freedom, torn apart by what exactly that "freedom" actually means.