"The engine of growth for the U.S. has been immigrants," he said. "They're the ones who take the chances, they're the ones who start businesses, and there's no difference really between the situation we're in today and what we were in the turn of the century, or other times in American history."
Glassman said arguments against reform on the basis of immigrants "taking American jobs" are "very weak."
"That's based on what's called the 'Lump of Labor Fallacy.' That is to say, there's only a certain amount of labor, and so if you're doing a job, somebody's going to take it away," he said.
If Congress fails to act or is unable to pass immigration reform, Glassman said, it will be years before there will be another "opportunity" and the current "failed immigration policy," if continued, would only serve to stifle U.S. economic growth.
"I don't think there's any doubt that continuing with the same failed immigration policy that we have in the United States today will continue to hold growth down," he said. "We really need to get this country up to 3 or 4 percent growth. ... I think [not passing reform] keeps us in the 2 percent range. And for the benefit of everybody in America, we need to grow faster."