Final answer:
Thomas Jefferson desired American exploration of the territory before the British or French to solidify American claims to the land, expand territory, secure resources, and identify trade routes.
Step-by-step explanation:
President Thomas Jefferson wanted the land explored by Americans before British or French explorers got there largely for strategic reasons. He believed that American exploration of the newly acquired territory would solidify American claims to the land, reducing the chances of foreign intervention. Jefferson desired to expand American territory and secure natural resources to sustain the growth of the country. The expedition was also intended to identify potential trade routes, specifically finding a direct water route to the Pacific Ocean for the purpose of expanding commerce. Ensuring that American explorers routed the land before their European counterparts was essential in maintaining America's claim and stake in the territory.
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