What was the main reason why jefferson was opposed to a manufacturing economy?

The main reason why jefferson was opposed to a manufacturing economy was because he knew that If big companies or financial oligarchies concentrate power, these would end up subjecting societies and even depriving citizens of their properties. He said that "if that happened, one day the children would wake up without a home and without a roof over the land their parents conquered".

Jefferson was against a manufacturing economy because the Constitution did not grant power to congress to make one. It would give the government too much power which would be dangerous because it would put all the economic power into cities.