There are no such things as rich nations and poor nations. There are rich and poor within nations. The rich collaborate with the rich regardless of nationality, while the poor are compartmentalized by borders, and are made to compete with each other as sources of labor, compete with each other to try to be the best producers of wealth for the rich.
A country’s president will talk about the national interest, but the interests he is actually serving have nothing to do with his nation; he is serving Samsung, Lafarge, Vodafone, Citibank, Bechtel, and so on.
National governments serving the foreign owners of capital, the global super-rich, in exchange for personal benefit. Yes, this degree of selfishness is betrayal. But I do not see a way to liberate any national government from this system except by popular struggle, not against their governments, but against the dominating influence of business over their governments.