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Global warming is causing drought, wildfires, and catastrophic weather right now. It will cause even more misery in the future. The people affected by these conditions are more likely to be poor and live in less affluent countries, but that doesn't make them abstractions.
Take a look at the two pro-slavery quotes in this article, and you'll see that both of them consider the slaves to be abstractions. We know that this does not mean that real people weren't being harmed by slavery.