Hard not be be impressed with Alan Greenspan’s thinking:
Education reform will take years, and we need to address increasing income inequality now. Increasing taxes on the rich, a seemingly simple remedy, is likely to prove counterproductive to economic growth. But by opening our borders to large numbers of highly skilled immigrant workers, we would both enhance the skill level of the overall workforce and provide a new source of competition for higher-earning employees, thus driving down their wages. The popular acceptance of capitalist practice in the United States will likely rest on these seemingly quite doable reforms.
Of course, brain draining other countries by importing the best workers probably will increase income inequality in the long term, all other things being equal, because a country with a higher average general intelligence grows faster and, thus, creates inequality faster. Still, when a country is rich it can afford luxuries such as public goods, universal health care, etc.