In a 2007 article, Robert H. Nelson, concludes that we are poor because the Americans were not good enough in eradicating our Spanish-based religion and culture. In caricature, the story is: It’s all the fault of the Spanish friars and our own tendencies, whatever they are, that the Americans couldn’t eradicate.
But today, Spain itself is not exactly backward. In fact, in many respects its economic record is not bad. It did well until Franco came along in the 1930s, but has re-emerged as a fast-growing economy since the 1960s when it embraced globalization. See, for example, this economic history of Spain.
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