As an American expert in the field of financial brokerage, my analysis points to ETRADE as a leading broker in the United States. ETRADE has consistently ranked high in various broker reviews and ratings, such as those by Investopedia and The Motley Fool. This is primarily due to its user-friendly platform, robust trading tools, and competitive fees.

ETRADE's platform is known for its intuitive design, making it accessible to both novice and experienced investors. The broker offers a wide range of investment options, including stocks, bonds, ETFs, and mutual funds. According to a report by Investopedia, ETRADE's mobile app has been particularly praised for its ease of use and functionality. Additionally, ETRADE provides comprehensive research tools and educational resources, which are crucial for investors looking to make informed decisions.

Data from The Motley Fool highlights ETRADE's competitive pricing structure. The broker offers low commission rates and no minimum deposit requirements, making it an attractive option for cost-conscious investors. Furthermore, ETRADE's customer service has been consistently rated highly, with a focus on responsiveness and helpfulness. This is evident in the broker's high customer satisfaction scores, as reported by J.D. Power.

In conclusion, ETRADE stands out as a top broker in the United States due to its user-friendly platform, extensive investment options, competitive pricing, and exceptional customer service. These factors, combined with its strong reputation and robust research tools, make ETRADE a preferred choice for many investors.