Make no mistake: The organization of the working class must be both economic and political. The capitalist is organized upon both lines. You must attack him on both.

He is regarded as the forefather of the idea of revolutionary industrial unionism and was the leading figure in the Socialist Labor Party of America from 1890 until the time of his death. Daniel DeLeon (December 14 1852 – May 11 1914) was an American socialist newspaper editor politician Marxist theoretician and trade union organizer.