Trading helped them rise since they were immensely rich in things like Salt which was even worth more than gold in many parts of the world. Having secure trade routes and taxing traders made the country rich and powerful. This led to the decline since such wealth meant that many foreign enemies would want to attack them and take it from them which is what happened to both Mali and Songhai empires.
Revelations that spies in the US atomic program had passed secrets to the Soviet Union set off a nationwide panic that communist spies might be infiltrating many American institutions.
Allegations that Hollywood was rife with communists led the House Committee on Un-American Activities (HUAC) to investigate many actors, writers, and directors during the 1950s. Alleged communists were placed on a blacklist and barred from working in Hollywood.
Republican Senator Joseph McCarthy took advantage of this widespread paranoia to advance himself politically by accusing State Department employees of communist leanings. McCarthy's accusations were unsubstantiated, and the Senate eventually censured him.
Answer:
The most important contributions is that the Byzantium Empire was able to preserve a lot of the knowledge and culture from the Roman and Greek Empires.
<span>When citizens are unhappy with a specific piece of legislation they want removed or struck down quickly, they can call a "referendum", which puts the issue to a direct vote by the citizens.</span>
