Even if the tumens (tyumens) were hundreds or thousands of miles away, the conquered people would usually not dare to interfere with the token Mongol occupying force since they feared a likely Mongol return. The reputation of guaranteed genocide on those who fought them allowed the Mongols to hold vast territories long after their main force had moved on. Thus, whenever possible, by using the 'promise' of wholesale execution in case of resistance, Mongol forces made efficient conquests, which, in turn, allowed them to attack multiple targets and redirect soldiers and material where they were the most needed. While both provided the same territorial gains, the former would continue to provide taxes and conscripts long after the conflict ended, but the latter would be depopulated and economically worthless once available goods and slaves were seized. Furthermore, a supine nation was more desirable than a sacked one. In the beginning, Temujin, the birthname of Genghis Khan, started off with a band of youths and some women, and he later had troops of 20,000 that initially faced the city states and interests of the Kin domain, which mainly included China, with then probably a 2-million-strong army, each city being populated with hundreds of thousands of inhabitants, and simply invading all of them was out of the question. The Mongols frequently faced states with armies and resources greater than their own. From the perspective of modern theories of international relations, Quester suggested, 'Perhaps terrorism produced a fear that immobilized and incapacitated the forces that would have resisted.' Although perceived as being bloodthirsty, the Mongol strategy of 'surrender or die' still recognized that conquest by capitulation was more desirable than continually being forced to expend soldiers, food, and money to fight every army and sack every place on the campaign's route. The success of Mongol tactics hinged on fear to induce capitulation of enemy populations. Invasion of Japan against samurai Takezaki Suenaga using arrows and bombs, circa 1293.

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