How have modern changes in the world made it way more difficult and almost impossible to isolate or separate yourself as a country from the rest of the world ?

propriety is the answer. hope this !

explanation:

the church governed the society after the empire fell.   constantine took charge of rome and ended the confusion which had over religion and made christianity as the only religion and that started ruling the roman empire. he also divided the empire into two and fortified the eastern part.   he ruled the eastern part.