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"In the perspective of world history, it is hard to imagine a combination of circumstances that would have prevented or delayed the European annexation of Africa."
"By the 1880s machine guns and light artillery capable of firing explosive shells gave the Europeans an incomparable advantage over any African opponent. Medical progress meant that European soldiers and administrators could be sent to tropical Africa without the old constraint of astronomical death rates from disease. Naturally, none of these changes could cause the conquest of Africa, but they slashed the price of any military action a European government might choose to consider, European economic growth made the cost smaller still in terms of resources available."