Final answer:
Samuel Gompers opposed allowing women to join the AFL because he aimed to focus the union's efforts on skilled, white male workers to efficiently achieve higher wages and shorter work hours.
Step-by-step explanation:
Samuel L. Gompers, the founder of the American Federation of Labor (AFL), opposed allowing women to join the federation primarily because he and the AFL were fundamentally focused on representing skilled, white male workers.
Gompers believed that by focusing on this demographic, the AFL could achieve its primary goals of increasing wages and reducing work hours effectively through negotiation and occasional strikes, without resorting to more radical or inclusive labor movements that included women, minority groups, or unskilled workers.
His approach to labor was more conservative than that of other groups like the Knights of Labor or the Industrial Workers of the World (IWW), and he sought to keep the AFL's efforts within the realm of what he deemed practical for those he represented.