As we have seen, the war of a conquest held a very specific place in salvation history, it was the only war Israel was ever commanded to participate in and it was the only war they ever won. This war was not an end in itself, but existed as a function of the possession of the Promised Land. Though the war was, in part, an enactment of God’s justice, Israel only took part because God commanded them to. There is nothing that gives licence for Israel to wage a war without a direct command from God.
The rest of the history of the Old Testament shows that God enacts his international justice without any involvement from his people – raising one nation to punish another. This does not make the nations’ actions good, or justify the wars that they waged. Rather, God is using the evil actions of people to enact his good purposes.
A faithful reader of the Old Testament, waiting for the Messiah, does not find themselves commanded to enact God’s justice on the surrounding nations – or even their own government. Instead, they are commanded to live lives of faithfulness and justice, and trust God’s sovereignty to care for them and bring about his justice on the Day of the Lord.