We don't need immigration, of course. If we were to end it tomorrow and get serious about the illegal variety our country would benefit immensly.
Immigration levels should be tied to certain benchmarks such as the unemployment rate. If it gets below a certain threshold then we could allow in a certain number, and even then it should only be the best and the brightest. As things stand now, immigration levels are basically uncapped and not tied to any real need -- and our crazy politiicans want to increase it even more!
Do companies just start hiring employees without any need for those hires? Why should our country be any different. The persistently high unemployment rate tells us that we don't have a need for any more right now.