I would describe Cambodia as an extreme example to use, because of its regime, its corruption and its abject poverty. But I could defend a right-wing point of view still:

A government is made up of people from a culture. The attitudes, opinions and behaviors of the government suggest something about the culture, and vice versa. Individual actions collectively form a culture, and vice versa. There is thus some culpability on the part of the culture for the kind of government you get, and vice versa. I feel it's fair to say that, to some degree, people get the government that they deserve. I think problems with the culture is the main reason why attempts to introduce a democratic form of government so often fail.

As for education and upbringing, they have some effect, but I think there is also a big element of personal culpability. In countries where market forces reign free, a characteristic wealth distribution tends to develop. A minority dares to gamble, and makes the decisions that gets it out of poverty, while the majority sticks to the safe old ways, and remains poor.

Socialism basically makes the argument that it's unfair that only a few people are crafty enough to find their way out of poverty, and seeks to correct it by taking from the rich (the ones who were crafty) and giving to the poor (the ones who weren't so crafty). The justification for this is that the not-so-crafty people can't help being who they are, and thus can't help their situation, so why should they suffer for this?

Capitalists argue that being crafty is a choice that you make, not a trait that you possess. You can choose to do something different than sustenance farming or underpaid factory work. There are always opportunities if you just look for them. Not looking for them, or not daring to make unorthodox choices, is simply lazy and cowardly. Because hard work and boldness should be rewarded (not laziness and cowardice), no wealth redistribution is required, because the market is already fair.

Even an uneducated farm boy can sneak in a few moments to learn things. It's not impossible to learn the alphabet on your own, or to find old books to read, and then learn to run a small business. There are many stories of people who have done that. People who lived in appalling conditions. Somehow, these people are seen as uniquely abled, but all they did was try something different and put a bit of effort into it.

Or so goes the argument of the free-market capitalist anyway.

In cases of serious, systematic discrimination against a group of people, it's a different story. A black slave in the United States did not have the same opportunities as everyone else. There was a deliberate and artificial limitation on what they could do, and one could argue that some of those limitations are still there in today's United States, de facto if not de jure. In such situations, it's no longer about the left wing vs the right wing, though, because no one wants oppression.