It's very clear that average IQ in the US has been in steady decline because of immigration from lower average IQ nations. The US will resemble something like Brazil where the whites live inside gated communities with 30 foot walls with barbed wire, their numbers dwindle as the country becomes even worse. The country will lose its status as the world leader in science and technology to East Asian countries. The same will happen to Scandinavian countries who opened up their borders 10 years ago.
Japanese and Chinese as well as other homogenous nations average national IQ remain similar.
National Geographic posted what the average American will look like in 2050