The immigrant experience is the foundation of America. In the preamble to the Constitution, we are told that we are forever moving toward a more perfect union. And the 40 million immigrants living in America today are a central part of making our union more perfect. The American Dream that is at the heart of the founding of this country is at the moment at risk. This country is based on the promise that if we work hard, we are going to do better and our children will do better still. That promise of upward mobility is no longer true for millions of immigrants in our country. America is...