A new study says that for the first time since the Great Depression, there may be fewer Mexican immigrants coming into the United States than there are moving from the United States back to Mexico. According to the Pew Research Center, the net migration between the U.S. and Mexico over the last five years was essentially zero, and the downward trend suggests that flow of both legal and illegal immigrants may have actually reversed back toward Mexico.

There are many possible reasons to explain the decline, but the most obvious one would seem to be the struggling U.S. economy, which has cost millions of available jobs, particularly in construction and in the South, where recent immigrants generally thrive. There have also been big increases in enforcement, deportations, and border security, although the report also says that arrests of illegal immigrants trying to cross the border has actually plummeted by nearly 75%. Whether that's because fewer people want to come here or they just don't think it's worth the risk is hard to pin down, but the number of folks willing to take the chance is definitely declining.

Given the continued hysteria over illegal immigrants and how demographic shifts might change the country in the future, many Americans might be shocked to learn that the shift is actually heading in the other direction. There have been several state laws just within the last couple of years that were passed on the premise that illegal immigration was out of control, even as the population of Mexican immigrants is apparently lower than it has been in decades. (Some might argue that the news laws are responsible for that, but the trend was clearly in place even before they were passed.) The Supreme Court will actually hear arguments this week about the harsh Arizona law that has been at the center of the debate for the last couple years, but this new evidence may put the crackdown in a new light, since the problem it was intended to resolve may not actually exist.