Question

what are three arguments as to what extent individuals or nations should care about the disparity of Human Rights in countries

Answer 1

I don't know whether there is an official list, such as from the UN, but here are some  arguments from me:

1. Individuals and nations should care about human rights in other countries because they often trade with other countries. If e.g. US buys goods produced with slave labour elsewhere, it still means that it supports (indirectly) slave labour

2. Human rights violations can lead to extremism and pottential terrorist activities: thus violence in one country can lead to violence in another

3. Countries should care about human rights violetions in other countries, because it can affect this country's citizens while abroad (recently an UK citizen was arrested for being homosexual in Morocco). 
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