Manufacturing costs are the main reason for man made borders. There needs to be certain areas where materials can be produced cheaply. Resources are another reason.

So called 1st world governments rob poor countries of their resources, using their own citizens. To maintain the dynamic they destabilize these countries’ governments and local economy, usually by arming and starting a war between opposing factions/tribes. Citizens of the “first world” are the beneficiaries of these odious policies. Then we have the nerve to want to “build a wall” to keep the victims of these policies away.

For Black people it’s even worse.

Africans mine diamonds, which are then traded on the open market without African countries profiting.
Then African AMERICANS buy them back in the form of blue-eyed Jesus pieces.

The confusion is truly universal