Pre-modern world having no borders is what gave birth to immigration into the said country & other parts of the world which got colonized over time. Kinda hypoc

Pre-modern world having no borders is what gave birth to immigration into the said country & other parts of the world which got colonized over time. Kinda hypocritical to suddenly have everything closed up. Who knows maybe space travel or resource scarcity is what unites all countries centuries down the line.