The problem, frankly, is that politicians don't explain the subject very clearly. I won't speculate as to why they don't, other than to note that the topic is rather boring for many people. However, it's important and because people keep asking this question, it deserves an answer. I've already talked a bit about how laws covering immigration and emigration often have little to do with the data, but importing workers into a high-unemployment area can make perfect sense.
|Image courtesy Wikimedia Commons|
The common rebuttal is "train them!" But this has several problems. First, businesses need these employees now, not after a years of training. So people say "OK, we'll patch the problem now and then invest more in universities to deal with this." Patching the problem now means importing highly skilled workers (or letting your businesses suffer).
People sometimes still don't believe this, but I'll give you an example. Years ago I was applying for a job with a small company that was nonetheless very well known in their field. The owner of the company was interviewing me and he showed me a custom programming language they had designed to make life easier for their customers. After glancing about at a programming language I had never seen before, I turned to the owner and asked him "do you know what an SQL injection attack is?" I showed two different vectors they had for it. He was stunned. He looked at me and said they had this problem for years but had only discovered it two weeks ago. I got a job offer out of that (which I declined).
Even if you train people really, really well in my field, most of them won't be able to do that without a plenty of experience (many top-notch devs read my blog, so it probably won't seem too remarkable a feat to them, but it is for someone who doesn't know the field). That's why your country may have high unemployment and highly skilled workers still get imported: we can bring immense value to an enterprise.
|Gratuitous cat picture|
I took this while on vacation in Corsica
In short, you need willing and qualified workers and the Universities aren't putting out enough of them, If you decide to beef up your university system, you then have to ask where that money's coming from and you have another political fight on your hands, but even after years of study, the graduates will still likely need experience in their field to get qualified. This is not an easy problem to solve.
Finally, you have the problem with economic growth. When I mentioned the example of your business needing to hire several new skilled workers, imagine a booming economy with thousands of businesses in the same boat. You can't supply the labor as fast as the market demands it. These people don't appear from nowhere. So either you turn your economic boom into a bust or you import the skilled workers. If you do import the skilled workers, your economy can continue to grow and offer opportunities beyond just the skilled jobs.
|My friend Paul messing about in the|
pool in the Corsican manor we rented