In WW1, the Japanese army only had to clean up what it could get from the German colonial possessions. Tsingtao was its biggest engagement and went well. It had not cost the lives of countless Japanese soldiers.
Contrast that to WW2, where you have an army that has been fighting in China since 1931 and then was thrust into the jungles of southeast Asia and the Pacific in a bitter fight for survival against the British and Americans. When you have spilled your blood, you are less predisposed to the gallantries of "civilized" fighting.
<span>And then you have the precedent of these exact same foes having turned down Japan's </span>Racial Equality Proposal<span> in 1920. The Japanese understood that the westerners were still looking at them as inferior. That resentment had time to fester in the intervening 20 years, among the ranks of the Japanese army officers.</span>
<span>Last but not least, in the interwar years the entire world saw a slide to totalitarianism, with Japan being no exception
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We can be sure that ancient civilizations knew of and were concerned about infectious diseases from several facts. The hunter gatherers rarely suffered from water borne diseases. They knew that the water that stank or did not taste well was not good to intake. Their main knowledge came from experience. During the Greek period several doctors like Alcmaeon of Croton were mentioned and hence they must have had the knowledge about infectious diseases like Cholera. Several other infectious disease treatment have also been mentioned during the Greek period.
<span>In the 18th century, Prussian ruler Frederick the Great emphasized military power to become an absolute monarch while also accomplishing doubling Prussia's size. Additionally, because he allowed freedom of religion, Frederick the Great is also known as an Enlightened Absolutist.</span>
Mostly, after WWI, Britain promised them their current stretch of land in the Middle East. While Britain did not deliver, this did give them their claims, and their holdings were secured in WWII and further legitimized in the current war on terror.