The strong institutional racism in the U.S. doesn’t need IQ tests to perpetuate itself, but those tests play a role in ‘scientifically’ reinforcing the idea that certain groups are inferior, whether the causes are genetic or not.
No one can deny the inequality in outcome for many people of color in the U.S., but many deny that there’s any inequality of opportunity, or that white privilege and structural racism exist. If the U.S. then functions as a meritocracy of sorts, any inequality is supposed to spring from something else, such as lower I.Q.s.
Steele found that the “root of black achievement problems is failure of American schooling to meet this simple condition for many of its black students”: “treatment as a valued person with good prospects.”
Source: The full scope of racial devaluation on economic opportunity – Long View on Education