The distinction between capital and labor perpetuates and absurd protectionism and is a major obstacle to economic growth. Immigration is a free trade issue.
Also, I come from the UK, which has more UK citizens working abroad than foreign citizens working here, all while some sections of the press runs stories about how foreign workers are crowding people out of jobs. I keep trying to ask people who support banning all foreign labour, what they think will happen when everywhere else bans UK labour from their countries in return and all those UK expat workers, with their wealth of experience, come flooding back in greater numbers than the foreign workers that have just been kicked out, so leading to even greater unemployment, while at the same time guaranteeing that nobody would really want to trade with us anymore. These kind of conversations often end somewhat badly for some reason.
Perhaps it might be because I tend to also mention the view that it is a bit rich for the UK to be complaining too loudly about immigration considering how big the empire grew from us going around and rudely sticking flags in other people's stuff.