The Monroe Doctrine became one of the crucial foundations of American foreign policy over the next century; what was the occasion for Monroe's articulation of this doctrine, and what were the circumstances motivating its adoption? What reasons were used by Monroe to justify this foreign policy pronouncement, and how do they relate to arguments made during the revolutionary and early republic periods?  

The Monroe Doctrine became one of the crucial foundations of American foreign policy over the next century; what was the occasion for Monroe's articulation of this doctrine, and what were the circumstances motivating its adoption?

The Monroe Doctrine came into place around December 1823. The President introduced the doctrine at that time, James Monroe, and this was done through the annual message to Congress. During this period, there was a massive movement within the Spanish colonies in Latin America towards independence. Therefore, the US was interested in preventing any other European power from stepping in. In essence, the doctrine had been introduced in attempts to ensure that the rights of the US citizens were protected.

What reasons were used by Monroe to justify this foreign policy pronouncement, and how do they relate to arguments made during the revolutionary and early republic periods?

In his message, President Monroe had argued that foreign policy was important as it acted as a tool that could ensure the rights of US citizens were protected (Scarfi, 2020). He further argued that the American Nation was still young and could not put up with any form of foreign interference within its territory. He was against any encroachment, especially by a European power, as it would disrupt the peace and happiness that the US citizens were enjoying at that moment.