According to the New York Post, Americans appear less intelligent to outsiders than citizens of other countries because its education system is lacking. A large majority of American adults score poorly on intellectual tests designed to measure problem-solving skills and mental acuity in areas such as mathematics, technology and reading. Sadhbh Walshe of The Guardian explains that this may be due to the country's income inequality.
Lower-income families generally live in poorer areas and are unable to provide a quality education to their children due to financial strain. Children born into these situations are also more prone to dropping out of high school, and they often fail to further their education in the future by receiving a general education diploma, or GED, or attending college. These children are regularly unemployed due to poor credentials, and it is not uncommon for them to remain jobless into adulthood.
Alternatively, the highest wage earners receive the best scores on international intelligence tests. Because of this, Walshe argues that income inequality is largely to blame for overall low intelligence, especially because poverty rates are on the rise as of 2014. While it is true that certain individuals are able to succeed despite their modest beginnings, Walshe states it is not the norm for most American citizens.