But millions of Americans DO care about soccer. Those with two-digit IQ's are crazy about American "football," but there are enclaves of soccer-mania in DC, Detroit, all over California, and elsewhere. If you add all these communities together, you would have a fairly populous "country" where soccer is at least as popular as, say, basketball.
I have nephews and neices who were playing soccer as soon as they came out of their mother's womb. They were competing as 4-year olds, going to camps. playing 11 months a year, in both school and traveling leagues. With thousands of other kids doing the same thing. Think they didn't care about soccer?