Judge, ‘shaphat,’ refers to the judge on the bench in a court of law. Jesus Christ will become the judge and will hear controversies and settle them.
These things will occur during the Millennium.
As for those who believe that the Millennium will begin and continue before the Second Advent, here is one of many verses that settles that argument. Jesus will not only be here physically, on this earth, and will rule, but will serve as the judge of nations, during the Millennium.
He can only do that while He is present. Otherwise no one could bring their complaint before Him to be heard.
Turning swords and spears into plows and hooks is an expression that indicates that society and nations will not prepare for war, ever again.
The economy will be a purely peacetime economy for the entire period of the Millennium.
During the Millennium, at its beginning, people will primarily live in or near Jerusalem, but as the population grows, then people will begin to migrate to the four corners of the planet, and nations will form.
Since at the end of the Tribulation, we know that the islands and continents will be changed dramatically, then we do not know exactly what the geography of the planet will look like. It could very well become one big continent, or have some other pattern.
We know that all of the mountains will be flattened and that Jerusalem will be the highest point. But beyond that, we do not know what the whole planet will look like.
As for the end of the Millennium, when Satan is released from his imprisonment, and leads those who have been negative toward Christ, against Christ. Then those folks will be advancing in huge numbers against Jerusalem, but they will not have any weapons. After a thousand years and no weapons have ever been made, then no one will know what to make nor how to make them.
And that leaves you wondering just what do they intend to do, and how do they intend to do it?
Satan is the principle instigator of evil, and lies and arrogance, and violence and so forth. While he is incarcerated, then humanity during the Millennium, will have no pattern nor anyone working in the background, to learn the ways of violent evil, such as war.
And so it will be, during that entire 1000 years. War, and the art of war, and the study of war and the materials of war, and the causes of war, will not exist.