The term “imagined communities” is used by social scientists to refer to communities that we think we belong to even though they are not really communities. Real communities are based on actual personal interactions. Imagined communities like the nation cannot be based on such interactions. When we feel that we are “Americans,” we cannot possibly be basing that feeling on any sort of personal interactions with every other American.
In the debate over immigration, imagined communities come into play because we think that we are connected to many people that we have never met and will never meet. We think of ourselves as members of the American nation and we think of many immigrants as members of some other community. We therefore want to have policies that will favor our nation. This nation is an imagined community of people who are in some way like us. We want our immigration policy to continue to favor the people who are like us.
Those of us who are Hispanic might consider themselves to be members of some community of Hispanic people and/or of immigrants. They will feel kinship to such people even though they have never met most of them and never will. Therefore, they support policies like the DREAM Act which would be beneficial to people of their imagined community.
In these ways, imagined communities can be very important in the debate over immigration in the US.