What was the biggest spark for the economic growth of the 1920s?

The biggest spark can be attributed to several factors, mainly the fact that the United States saw large revenue from World War I and the supply of weapons and materials to other countries. Another was the business and economic friendly policies of the Republican Party and its presidents that were in office during the 20's, coupled with our industry taking off during this time period

The central idea is that the hiv/aids epidemic is serious.