A bit of a sideways question: if we are going to care about the suffering of people we've never met, why does it matter which side of the UK border they are on?
I think it shouldn't. I don't think someone living in poverty anywhere else in the world is less deserving of help. And there are plenty who are in greater need and have no prospect of help from their own governments.
People discuss the extent of UK socialism as though it were a moral issue, yet a rational approach to taxing the UK better-off for the moral purpose of helping poor people they have no direct connection to would see most of the money go abroad, and the UK benefits system and even the NHS both possibly abolished, to free up money to go abroad.
To give a random illustration: A rational and moral approach might see not a single UK person funded for cancer treatment until there was no community in the world without safe drinking water.
It's tempting to think people who are angry with the meanness they perceive in UK socialism are hypocrites, cynically serving a UK left-wing agenda. Or maybe xenophobes, who value a British life more than an Indian or African one. However I know that would be wrong. Like religious believers, they were simply born into a belief-system that only makes sense when viewed from inside. They can't help their moral myopia.
(I won't actually abolish UK socialism when I'm dictator, however in the meantime I don't defend it as a moral enterprise. I suppose my reason for keeping it would be because it would be possible to derive more visible progress from perfecting it, which would be more satisfactory psychologically. Like someone who only tidies the tidiest room in the house, the one they spend most time in, while mentally trying to block out the mess everywhere else.)
(I'm not claiming the moral high ground. I just wish everyone else would get off their high horse, as their moral superiority is a figment of their limited imagination)