Ulysses S. Grant – 130
Considering that the ‘least smart’ president on this list still has an IQ of 130, which is 15 points above average, you can get an idea of how smart American presidents are. After graduating from West Point, he proved himself during the Mexican-American War. At 47, he became the country’s youngest president. On moral authority, international relations, public persuasion, and seeking justice for everyone. The public remembers him as an honest man who opposed the KKK. His appointment of African-American and Jewish-American officials was equally notable.