That is hardly it... The US population largely agrees that the military budged is way too bloated, that infrastructure spending is way to low, and there is a general lack of a single payer health care system and tuition free public schools.
I’m sure you’ll find way more happiness towards paying taxes in the UK and China then in the USA despite being as diverse and even larger then the USA.
US is vastly larger. New York City alone has 3X as many public school students as Iceland has people. We are vastly diverse ethnically, culturally and geographically. It is much harder to find "problems and solutions everyone agrees to" in the US than in Iceland.