This group included many labor union members, and actively opposed the draft during WWI.

Socialism  

Explanation:  

Socialist were members of labour Union which formed before the war began in Europe. They opposed the war because they saw people killing each other in the interests of their leaders. Socialist party in America, Germany, Italy, and Bolshevik (Russia) opposed the war. They actively opposed the draft during World War I. Socialist parties in the countries like New Zealand, and trade union in Australia opposed as they believed to replace foreign labour in their country. In America, activists published magazines and newspapers, held parades, plays, and demonstrations to show the danger of war and to stop entering into it.

its main object was the establishment of "settlement houses" in poor urban areas, in which volunteer middle-class "settlement workers" would live, hoping to share knowledge and culture with, and alleviate the poverty of, their low-income neighbors.