Why Was Rome Responsible For The Fall Of The Roman Empire?

Averill Cameron claimed that even though barbarian attacked on Rome, they were not responsible for the crisis. Internal political, social, Corruption and economic problems were primarily responsible for the fall. On the other hand, Derek Williams stated that barbarians’ tribes were the main cause of the Roman Empire fall.
At that time there was no police force, no law system or bank system. Also, a large majority of population was not working for wages. Also since people of Rome were unemployed they were not able to give tax to Roman Government which is why Roman Empire lacked wealth. People worked for landowners. In contrast, if there was no advanced military, then barbarians would take over them. Obviously if opposition doesn’t have good military, then they would be easily taken over by the barbarians. Lack of wealth was also one of the reasons why Roman Empire did not have an advanced military.
In any case, the degree to which ancient agricultural writers are a reliable guide to real economic activity at any period is itself problematic. In view of barbarian commercial addiction we may imagine the empire’s neighbors under acute stress, with Rome comparable to a drug dealer who becomes so involved in gang feuds that he forgets to supple his customers. However, the migratory fluxes, which signaled the destabilization of central and Eastern Europe, required an outside push to give them irreversible motion. Averill Cameron impressed me as being the most empirical in presenting her thesis for the reasons that she had back up arguments, good statistics, and she was straight forward with her