The current US population is 7 billion, US population is 300 million. How many of the 6.5 billion non-Americans do you think could be rapidly absorbed, both te

The current US population is 7 billion, US population is 300 million. How many of the 6.5 billion non-Americans do you think could be rapidly absorbed, both terms of infrastructure (roads, water, sewers) as well as housing, culture, and government subsidies? Your answer MUST be expressed a NUMBER, not some vapid BS platitude.