Final answer:
Thomas Jefferson authorized the Louisiana Purchase due to the economic opportunities and geopolitical advantages it provided, including control over New Orleans and the Mississippi River, despite initial constitutional concerns. The desire for westward expansion and agrarian land for the populace, as well as acquiring the territory at a bargain price from France, were key reasons
Step-by-step explanation:
Thomas Jefferson was persuaded to proceed with the Louisiana Purchase predominantly because of the economic opportunities it presented, as well as the strategic geopolitical advantage it would afford the young nation. While he was initially concerned about the constitutionality of the acquisition, Jefferson was able to reconcile this by focusing on the broader goal of an agrarian society and the benefit of controlling crucial territories like New Orleans and the Mississippi River, which provided vital trade routes to the rest of the continent. Additionally, the potential for westward expansion of the country and the agrarian dream of having farmable land available for the masses were driving factors in his decision to authorize the purchase. The fact that the land was available at what Jefferson considered a bargain price following the retreat of Napoleon's ambitions in the Americas due to the Haitian Revolution further sealed the decision, and through his proxies, Robert Livingston and James Monroe, the United States doubled in size with a purchase of just $15 million in 1803.