I agree with most of what Tony Blair says in the article, especially this paragraph:

“Of course it has to be controlled, and illegal immigration has to be tackled head on. It's important that we do that,” he said. “But overall I would like to say that I think immigration has been good for Britain and most immigrants have assimilated well. So don't make them a scapegoat for our problems.”

In my view, immigration has definitely been good for Britain. Without it, we really would be in trouble!