I think, (and hope), that if I were to express my concerns on immigration face to face with some of those who disagree with me most on here, that we might have a more meaningful discussion. And likewise, if they were to speak in a calm and respectful manner, as I assume they would to me in person, that I might stop and think more about their comments on immigration too.
Tapping opinions behind a keyboard often makes everyone seem more aggressive and confrontational. Obviously we can't on GN, but engaging in constructive dialogue tête-a-tête would ensure that both sides - because sides is what it amounts to - might fight less and be less hostile. It certainly couldn't be worse than what goes on online.
I have many heated discussions with my French friends over here, (about each country's flaws), but often we say things with humour in our eyes or gestures to lighten what could become unpleasant. I think it would come across very differently on a keyboard.