Can We Feed Nine Billion People? Should We?

Projections show that the global population will reach seven billion people by the end of 2011, and will exceed nine billion by 2050, with much of this growth occurring in the least-developed countries, where a high rate of mortality is outweighed by an even higher rate of fertility. Past trends indicate many of these people will try and migrate to the wealthier countries in Europe and the USA. The US population has doubled over the last fifty years, much of it from immigration. What would the US be like if in fifty years we have a population of 750 million, much of it from immigration?