Contradiction with Ecclesiastes 3:8
Ecclesiastes 3:8 states there is a time for war and a time for peace, which may imply that continuous war isn't always appropriate.
Ecclesiastes 3:8: A time to love, and a time to hate; a time of war, and a time of peace.
Contradiction with Matthew 5:9
Jesus blesses the peacemakers, suggesting that peace, not warfare, is the ideal.
Matthew 5:9: Blessed [are] the peacemakers: for they shall be called the children of God.
Contradiction with Isaiah 2:4
Isaiah prophesies a time when nations will not take up arms against each other, which is a vision contrary to the lengthy wars described in Joshua.
Isaiah 2:4: And he shall judge among the nations, and shall rebuke many people: and they shall beat their swords into plowshares, and their spears into pruninghooks: nation shall not lift up sword against nation, neither shall they learn war any more. [pruninghooks: or, scythes]
Contradiction with Romans 12:18
This verse urges believers to live peacefully with everyone as much as possible, which contrasts with persistent warfare.
Romans 12:18: If it be possible, as much as lieth in you, live peaceably with all men.
Contradiction with Psalm 34:14
Advises to seek peace and pursue it instead of engaging in prolonged conflicts.
Psalm 34:14: Depart from evil, and do good; seek peace, and pursue it.