One of the stranger arguments put forth by defenders of Arizona's SB 1070 immigration law is that the federal government isn't "doing anything" about illegal immigration. This is belied by, among other things, the aggressive nature of the Secure Communities program, which, notwithstanding rhetorical objections about forcing local authorities to enforce immigration laws, compels local law enforcement to forward identifying information from arrests to Immigrations and Customs Enforcement, which then uses the data to find and deport undocumented immigrants. Homeland Security officials once described the program as voluntary, but that was before states tried to opt out. Then they turned around and said it was actually mandatory.
At any rate, Secure Communities is meant to symbolize the administration's commitment to removing noncitizens who pose a serious public-safety threat. But the vast majority of the undocumented immigrants deported through the program have been previously found guilty of either minor offenses or nothing at all. My former colleague Renee Feltz and her partner Stokely Baksh have put together a rather amazing infographic explaining how the program works and who it has ultimately ended up targeting for removal, which you should really check out, because I'm going to be linking to it a lot in the future.