The technologies developed by the dominant western powers would enable them to stay on top for much of this time period (1875-1914). Clearly weaponry was a key factor. The British were not the first to use firearms since gunpowder was invented in China. However, they were the first to invent the deadly machine gun that would change the face of warfare forever. The Maxim machine gun was revolutionary in that it enabled a small force to defeat larger (less developed) armies. It would have been impossible for the powerful west to stay on top without the aid of such technologies.
Another key invention was the steam engine and more specifically the railroad systems. Not only did this spark commercial integration and growth. It connected vast parts of the world together. Where once it took weeks to travel across open continents, it was then shortened to days or even hours. The railway technologies that helped to advance the West were brought to their colonies and vassals. A classic example is the construction of railways in China. The rail system there was not for China’s advantage but for Western capitalists. The rails were designed to carry materials from the interior of China to the coast. Their purpose was not to link parts of China together for the use of the Chinese people but rather was used to facilitate faster acquisition of their natural and manufactured goods.
Over time technologies are then incorporated in the host countries for their own good but this happened after their overlords left.