There were many factors that played a role on the decay of the United States of America: 1. * Economic recession/depression 2. * Military competition 3. * Internal unrest 4. * Too many people to rule over 5. * Opposition from non-Westerners 6. * Disease epidemics 7. * Secessions of various non-recognized states 8. * Loss of allies as they also dissolved 9. * Lack of national will