Despite all the propaganda they flaunted around, colonial powers rarely felt anything similar to a moral responsibility towards the improvement of their colonies. For example, take the British in what was the jewel of their colonial empire. All the "improvements" the British colonial authorities made there (irrigation canals, railroads, etc), including defense spending, was financed exclusively by the Indian taxpayers, independently if that spending would benefit the Indians or not. For example, during the 1876-78 famine in the Deccan, the colonial government refused not only to help its starving subjects, but they refused to lower taxes and even increased them in order to guarantee that the oncoming Afghan campaign would be entirely paid for by the Indian budget, without touching the British taxpayers' pockets. And that's not an isolated happening, but the regular order of things in European colonies. The French rule in Algeria prompted a 50% decrease in native population levels between 1830 and the 1880s, the Dutch instituted a near-slavery plantation system in Java, etc.