FULL ANSWER
Because the Industrial Revolution increased the production capacity of Western states astronomically, there was an enormous hunger for raw materials to satisfy demands. Thus, Western powers sought colonies where raw materials were abundant and where they could be appropriated at little to no cost. Additionally, colonies gave the Western powers a ready-made market for their goods, as the colonized people were left with little to no legal recourse to produce their own finished products. Technological advances in Western arms and transportation commonly made indigenous resistance to imperial incursions futile and short-lived, as Westerners had far superior weapons, ammunition, strategy and tactics.
It symbolizes the readiness of the United States to protect
its territories with the use of force if need be. After its westward expansion, the U.S. was
now able to exert its full authority in the continent and made it clear that it
would not tolerate any interference from outside countries on its territories.
In France following the French Revolution there was a period that is known as the "reign of terror" whereby revolutionary courts were set up to prosecute individuals who were believed to be "enemies of the revolution." This was essentially a witch hunt for the enemies of the political elites during this period.
