I think it has more to do with the fact that innumerable amounts of people abuse the current citizenship laws of the United States. Many people come here to simply give birth to a child and get US citizenship. Think of it as a loophole. These people circumvent immigration laws and as a result, it only encourages more people to do so as well. What's the point of waiting to legally immigrate when you can just come here and pop out a child and have them sponsor you. We are a nation of laws and they must be obeyed. Without laws we have anarchy.