In this economy, it could well make a difference to them. They need jobs and are already competing with immigrants, legal and illegal.
Union members don’t compete with illegals, immigrants or blacks. They’re part of the same political coalition and that’s why things like affirmative action and set asides don’t bother them. You have to give to get. They also don’t tend to get the concept of free enterprise. I live in western Pa and it has a good job market so the local union idiots aren’t feeling much pressure. On the plus side, I must say they aren’t sporting the Obama bumper stickers on their trucks like they did the last time.