From what I know of the book, it was a critical success but did not resonate with the public the way Sinclair wanted it to. The government took notice and tried to better regulate the meat industry. Working people, however, were not drawn to it the way had hoped.
People came for a variety of reasons, including economy, adventure, health, and philosophical notions such as Manifest Destiny. During the early 1830s affluence, Americans gambled heavily on the land, resulting in the Panic of 1837 and the following downturn.
In the context of World War II, the 'Big Three' consisted of the leaders of the three most powerful countries on the side of the Allies. They were Winston Churchill, the Prime Minister of Great Britain, Franklin D. Roosevelt, the President of the United States, and Joseph Stalin, the Premier of the Soviet Union.
https://study.com/academy/answer/who-were-the-big-3-in-world-war-ii.html
Three dominant personality traits would be extroversion, sensitivity, and compassion.
