Oil Takes Center Stage
By 1910 Germany had become the industrial powerhouse of Europe. It's interior lines and extensive railroad system also gave it crucial advantages in any potential conflict. What it didn't have was the extensive system of overseas colonies possessed by Britain and France, and it lusted after them. Since at that point, most of the colonizable world was already in one pocket or another, that meant grabbing colonies others already controlled. The biggest obstacle was the British fleet, so Germany set about building its own.
At that point, oil had already become one of the worlds most valuable commercial commodities, used for lamps, motorcars, and numerous other things, but the British fleet ran on coal, and armies moved by rail, horse, and on foot. When Germany made some crude intimations of a move toward Africa, the new First Lord of the Admiralty, Winston Churchill, was quick to recognize the threat, and embarked on an ambitious program to build oil powered battleships: faster, longer ranged, and more easily refueled.
World War I led to explosive development of the internal combustion engine and especially its applications: not only ships, but motorcars, motorcycles, airplanes, and the tank. The ability of the Allies to deny Germany access to oil, while protecting its own sources of oil from the US, Indonesia, Persia and other sources proved crucial to victory.
By the end of the war, oil had moved to center stage of both world economy and world strategy. Obtaining sufficient oil became the central thrust of international strategy.