If you think about what 1970s "middle income" jobs looked like, they were mostly factory jobs that paid well. Nowadays those jobs don't exist due to deindustria

If you think about what 1970s "middle income" jobs looked like, they were mostly factory jobs that paid well. Nowadays those jobs don't exist due to deindustrialization. So you can't really blame that income inequality on domestic US social policy when a big portion was due to US foreign policy.