Thomas Jefferson believed that industrial manufacturing would threaten the agrarian lifestyle. He argued for maintaining agrarian farming practices, or what he called the "agrarian ideology," in his Notes on the State of Virginia (1781).
Thomas Jefferson was not opposed to industrialization in principle. Rather, he argued that if manufacture were to have any function in the American economy, it should merely supplement agrarianism, not replace it. Later in his political career, Jefferson recognized the need for some industrial manufacturing. In particular, he realized that it would be a necessary aspect of participating in the War of 1812.
Jefferson believed that agrarianism was of greater inherent moral value than industrial manufacturing. "Those who labor in the earth are the chosen people of God," he claimed in his notes of 1781. "While we have our land to labor then, let us never wish to see our citizens occupied at a workbench, or twirling a distaff." Moreover, as a matter of principle, Jefferson argued that industrialization created dependency, whereas agrarianism allowed men to retain their self-sufficiency.
The Louisiana Land Purchase of 1803 was part of Jefferson's plans to create an agrarian nation of self-sufficient farmers. Though the purpose of the Lewis and Clark expedition that followed the purchase was to explore viable water trade routes through to the Pacific, it was also to document what kinds of land, vegetation and animal life characterized the newly purchased tract.