Some or even all that the professor says may be true, but there is a bigger point to debate. At the federal level, and possibly at the Arizona state level, there are people being paid to determine immediate and future needs for many things- roads, services, and people needed in the private sectory to do the jobs that exist today and in the future. To a degree, this is managing population change, positive or negative. When the government, state or federal allows people to enter the country or a state willy-nilly, you create the situations that the professor describes. Therefore, the federal government should be managing the needs of our country by continuing to analyze and predict population/immigration numbers, without bringing political bias into the analysis. The federal government has shown/demonstrated an inability to do very few things correctly. Therefore, Arizona has the duty and the right to do whatever they believe to be in the best interests of the citizens of Arizona. Case closed.