1.http://en.wikipedia.org/wiki/List_of_African_countries_by_Hu... 2.http://en.wikipedia.org/wiki/Human_Development_Index
Related: http://www.stratfor.com/analysis/geopolitics-united-states-p...
Righting a terrible, terrible moral wrong should come regardless of the short-term economic costs. To suggest that economic concerns trump overturning codified racism is one of the most disheartening things I've read on this site. (I do hope I've misread your comment as a support of apartheid.)
2. His point- that certain countries were much better run while colonized still stands (check out Zimbabwe for example).
Take Africa. Given that there were only two uncolonized countries, the sample size there is too small to be meaningful, though the fact that neither Liberia nor Ethiopia fall into the lowest group of African countries in terms of either HDI, and there are a number of countries below both in Africa that did fall under colonial rule (Central African Republic, DR Congo, Malawi, Burindi below Liberia, plus Niger, Mozambique, Eritria, Guinea, Togo, Madagascar, and Guinea-Bissau below Ethiopia), would seem to indicate that colonial areas can be quite bad off.
Lets also look at your example of Hong Kong. The issue there is that you're conflating a single city, one that was used as primarily a trading and financial hub for the British Empire, with an entire country. Cities across the world tend to be more prosperous in general than the rest of the country. Plenty of Latin American capital cities are quite modern, and many other coastal Chinese cities are as well, but that belies the widespread poverty that might exist in rural area.
Problem is, that doesn't reflect the history of Liberia at all, which was colonized and established in 1822 by Americo-Liberians.
By what metric (child mortality, water quality, GI diseases, environmental degradation), could you possibly undermine this statement? Africa appears dirty and diseased because it is.
"Africa harbors exotic diseases" - fact
"IQ tests have conclusively shown there are differences between races" - fact
"The observed difference in IQ between races are because race X is genetically inferior" - causal speculation