Scholars and politicians disagree on this question, and both sides have arguments of value. However, the attitude most democratic countries have adopted is that of thinking they DO have responsibilities towards less developed countries. They provide several arguments for this position:
Most developed democracies engaged in colonialism. The countries that were colonized provided colonial powers with resources and a labour force that contributed to their development. Therefore, rich countries developed at the expense of developing countries.
A related point is the fact that after decolonization, most powers left without any plan to maintain order. The chaos they left behind has made it difficult for some countries to recover (often including the destruction of previous culture, values, ways of government, etc. that used to maintain order in the communities).
The Earth's resources belong to all of humanity, and redistribution is justified on these grounds.
A humanitarian argument. We have a duty to help those people who are suffering, regardless of whether they are our neighbours or not.
