Immigration Reform and Presidential Politics

"Comprehensive immigration reform" was a promise of Barack Obama's first presidential campaign. Now he's returned to it as he tries for a second term. With Americans in a state of high anxiety over unemployment, that means finding economic arguments for welcoming newcomers into the country. Has President Obama been tough enough on border control, or too tough? Does reform have a chance with Congress so polarized before next year's elections? Will the courts allow states like Arizona to make immigration policy the federal government can't or won't?