Bell was a life-long critic of black emigration programs, particularly the proposals by the American Colonization Society to settle free black Americans in Africa. He argued that African Americans should remain in the United States and demand their rights as American citizens. He advocated political action to achieve these rights, and as a leader of the New York Political Association in the 1830s, he urged blacks to organize petition and lobbying campaigns to expand their voting rights. In the 1850s he continued to work for black enfranchisement through the black state conventions and the New York State Suffrage Association.
Bell's most notable achievement was his pioneering work in the development of the African-American press. His career in journalism spanned over fifty years, beginning in January 1837 when he was editor and proprietor of the New York City Weekly Advocate.