But then you should call the thing to be solved "problem of good governance" instead, and that is something that indeed may take centuries. Bad governance will manifest itself in a multitude of problems that have no intrinsic organic relationships amongst them, and I am not sure if it makes sense to split them into sub-categories.

In the past, hunger was quite often a quantity problem. If a period of bad weather hit Medieval Europe, there wouldn't be any practical way how to import food for the entire continent from, say, India.

In this sense, hunger is being solved.