Pentagon, twin towers, and one other thing.
Answer:
The 1956 flag was adopted in an era when the Georgia General Assembly "was entirely devoted to passing legislation that would preserve segregation and white supremacy"
Explanation:
World War I, which lasted through Jul 28, 1914 to Nov 11, 1918.
https://www.history.com/topics/world-war-i/world-war-i-history
Info at the link
In the United States, the three main factors that make up the system of checks and balances would be the Executive Branch, the Legislative Branch, and the Judicial Branch, since the goal is to separate these powers so that no single power becomes too powerful.