The rhetoric that surrounds immigration is rife with protectionism, the same protectionism that has plagued the US forever. Whites were fearful that blacks were going to take "our jobs" so "prevailing wages" regulations were enacted to make it harder to hire blacks.
After WWII it was women that were taking jobs away, so Congress enacted minimum wage laws to protect men against the new low-wage entrants to the work force. Fortunately these protectionist schemes didn't work and we became a wealthier country in spite of attempts to maintain the status quo.
Change is hard, but change is what drives progress forward. Can anyone honestly say that we would be better off today if we had succeeded in protecting "our" jobs from blacks and women? The circumstances today are identical to the circumstances of yesterday, merely the faces have changed.