What section do US became a leader in the manufacturing and commerce?

The United States became a leader in manufacturing and commerce primarily during the late 19th and early 20th centuries, particularly in the industrial sector. The rise of factories, advancements in technology, and the expansion of the railroad network facilitated mass production and distribution of goods. Additionally, the development of a consumer economy and innovations in business practices, such as assembly line production, further solidified the U.S. position as a global economic powerhouse. This era marked the transition from an agrarian society to an industrialized economy, setting the stage for America's dominance in global trade.