This is because the issue is not packaged as one that is a crisis for us, but for them. Democrats have haphazardly pushed for pathways to citizenship for migrant workers, which Republicans have vehemently rejected in Congress. A little time passes, and the process is repeated but it never builds momentum.
Many believe that the current age of technology keeps us more connected. I disagree. Computers, cellphones, iPads, etc. serve a purpose, but it's not to keep us connected with each other. The disconnect amongst people is startling. Instead of interacting with a real, live human being, we read emails or texts. Or, perhaps we read a blog. We're far more attached to technology than people.