The kingdom of God becomes clear when conflict and violence stop. It is characterized by peace (Romans 14:17). People will either choose to cooperate or be compelled to stop fighting (Psalm 46:9). Nations will choose divine judgment instead of war (see Isaiah 1:18–20).
The words judge and arbitrate describe God's actions here, but later verses show the Messiah as the one who delivers justice (Isaiah 11:3–4). When this happens, war will end, and nations will turn their weapons into farming tools.
swords into plowshares: Compare Joel 3:10, where nations are urged to beat their plowshares into swords.