It usually pays to be skeptical about immigration reform, given the alliance between nativists and labor unions for tighter borders. Still, an economic downturn is the right time to move on immigration, one of the few policy tools that could clearly boost growth…

There’s a strong case that we need both more skilled and unskilled immigrants. In “The Venturesome Economy,” Columbia business professor Amar Bhidé showed that wherever technology is developed, it’s the creative application of innovation that builds great businesses. The Web was conceived in a lab in Switzerland, but it matured in Silicon Valley. Mr. Bhidé argues that immigrants at all levels, including as “venturesome consumers,” are an important reason the U.S. retains a strong lead in innovation, even as the lead in advanced technology and science has eroded.