Connolly was in line with socialists over WWI
Connolly viewed the conflict as an imperialist adventure by the capitalist nations, and argued for the European working class ... to stand united in opposing the war, and fight instead for international socialism. While he argued that if the German army invaded Ireland, the Irish would be justified in fighting with it against the British Empire, this should not be confused with support for German imperialism. He continued: “Should the working class of Europe, rather than slaughter each other for the benefit of kings and financiers, proceed tomorrow to erect barricades all over Europe, to break up bridges and destroy the transport service that war might be abolished, we should be perfectly justified in following such a glorious example and contributing our aid to the final dethronement of the vulture classes that rule and rob the world.”
Connolly was adopting a position in line with that taken by revolutionary socialists across Europe, the US, Australia and elsewhere at this time.