Final answer:
Individuals other than leaders might call a halt due to leader absence or incapacity, misguided or dangerous actions by leaders, crises requiring immediate local decisions, or strategic necessity in historical and military contexts.
Step-by-step explanation:
There are several historical examples where individuals other than the designated leader had to call a halt to an action or a decision that impacted a significant number of people. One primary reason might be the absence or incapacity of the leader, as in this case when Stalin "had shut himself away from everybody, was receiving nobody and was not answering the phone" during a critical period. Another reason could be when the leaders themselves might be pursuing courses of action that are seen as misguided or dangerous, and subordinates or secondary authorities feel compelled to intervene to prevent further harm. For example, during World War I, some leaders continued with the hostilities due to a firm belief in ultimate victory and the fear that ending the war might fuel the growth of Socialism, despite the enormous human cost.
In times of social unrest or when a crisis emerges such as a natural disaster, political figures who are not necessarily the main leaders, such as governors, may have to make decisions that can affect public safety. Moreover, in military contexts, if certain strategies can lead to disastrous outcomes like in the example, "the leaders of all your three divisions will fall into the hands of the enemy," a subordinate may have to call a halt to prevent such a scenario.
Finally, circumstances might demand that someone other than the leader steps up due to the strategic importance of the situation, like seizing control of a trade route or managing an alliance. In this way, halt decisions can emerge from a complex interplay between strategic necessity, political pressures, and human costs.