Why have immigration reform laws become increasingly more pressing issues during presidential elections in the last decade?

Question to write paper on: why have immigration reform laws become increasingly more pressing issues during presidential elections in the last decade?

This paper should give an educated opinion/answer on this question and back it up with lots of evidence and sources. it should also compare/contrast existing opinions/articles on the question throughout the paper.

Comparative Research Paper: For this research paper, you will try to answer your ‘Why’ question about some aspect of world politics. Ask: How have political scientists tried to answer this question?

What do you think is the answer to this question?What evidence would you need to collect to answer it? In order to develop your own argument,you will compare two (or more) cases in a most-similar-systems (MSS) or most-different-systems (MDS) research design.