It seems that Paul Collier has left out a major component of inequality and inconsistency in international development - what about race?
Collier posits that the US got serious about international development for post-war Europe in the 1940's because we 'knew [we] had to'. It does not seem compelling enough to suggest that competition for dominance in the World against the rising Soviet Union accounts for US post war development success in comparison to its failure in Africa. During that time of pre-Cold War competition, the US' development of Europe was still uneven in comparison to it's efforts to compete with the USSR for the hearts and minds of nations in the non-white world during the very height of the Cold War. The United States provided arms to countries in the Middle East, Central Asia, the Caribbean, and went to war in South East Asia (for strategic reasons), but it did not enact the kind of 'Marshall aid' initiatives around the world to same extent that it did for post-war Europe. The respect for sovereignty, the effective rebuilding of destroyed nations in Europe, and the sense of obligation are unparalleled to this day, by any effort in the non-white world.
It is simply not enough to say that the US 'knew [it] had to'. Many people make the same argument today about Sub-Sahara Africa, South East Asia, and the Middle East; that the West is in an even more heated competition for the hearts and minds of the world's bottom billion against extremist, post-colonial schools of thought, most notably Islamic Extremism. Still our efforts in those hotbed battlefields of Nigeria, Somalia, Ethiopia, Saudi Arabia, Pakistan, etc are met with the continual support of pseudo- or anti-democratic leaders, met with half hearted and far-from-Marshall aid plans. However, we have spent millions on countering terror threats and not on development, even though the two are tied. The difference is racial. Westen nations have a sense of obligation to one another through the remnants of racial unity and the distant pity for the non-white world fails to close the chasms of colonially constructed racial world landscap