There are several reasons experts believe the city of Cahokia disappeared such as:
It grew too large
Sanitary system wasn't good and people got sick.
Inhabitants destroyed the nearby forests to get firewood and without the wood, their city couldn't survive.
Enemies attacked.
Cahokia was a thriving city that was quite prosperous with their main food being maize which the fair climate allowed them to grow.
Overtime this changed and a drought that lasted for centuries kicked in. It led to conflict and strife in the large settlement as people could not get enough food.
Experts also believe that other problems such as poor sanitation systems and enemies attacking may have also contributed to the inhabitants leaving.
In conclusion, Cahokia was large and thriving but faced many challenges that in the end led to it collapsing.
Karl Marx once said; "I am not a Marxist!". He also once called his adherents "useful idiots". Karl Marx presented a strategy in communism much of which can be found in his book, Das Kapital.
