The main part of the U.S. economy is the service sector, which includes a broad range of industries such as healthcare, finance, real estate, professional services, education, hospitality, and many others.

Some key points about the service sector’s dominance in the U.S. economy:

1. Services account for around 80% of U.S. GDP and jobs. This has been the case since the late 20th century as the economy transitioned away from manufacturing.
2. The largest service industries by GDP contribution are real estate, healthcare, professional/technical services, finance/insurance, and government services.
3. Major service hubs include metropolitan areas like New York (finance, professional services), Los Angeles (entertainment, tourism), and Washington D.C. (government services).
4. Employment in the service sector has grown steadily over decades, while manufacturing jobs have declined due to automation and offshoring of production.
5. Services are generally harder to automate fully compared to manufacturing, contributing to their large workforce footprint.

While the U.S. remains a major manufacturing power, particularly in areas like aerospace, automobiles and petrochemicals, the service economy now overwhelmingly drives national output, employment and growth. This transition mirrors broader economic shifts in other advanced economies.