I don't know how you interprete it but I believe it is in the days of millennium reign of Christ on earth that nations will stop to learn war and will turn their spears into agricultural implement!
[[Isa 2:4]] KJV 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.

Do you think of another interpretation?