The correct answers to these open questions are the following.
What has made America thrive over the past 100 years so much? Why do you think it is the country that is known for the "American Dream"? What do you think could cause the dream to come crashing down?
Well, I consider that what has made the United States thrive over the past 100 years has been a combination of the following factors. First, American people have an inherited culture of hard work and commitment to thrive and prosper under difficult conditions. That is how the first English colonists thrived when founding the 13 colonies on the East coast of North American territory.
The other factor is that through developing the military industry and armed forces, the US has been capable of controlling some political and economic interests abroad. Particularly, oil and gas.
The US is the country that was considered in the past as the American Dream because every immigrant that came here had the opportunity to make a good living or being rich through hard work. It was known as the land of opportunities.
Today, there are countries such as China, Germany, Sweden, Denmark, Norway, or Switzerland, that offer better opportunities, and have better economies.
And that is the part of the crashing down. The US has many issues of concern in its politics and social life. Internal political disputes, a nation divided, the economy facing problems, poverty, government debt, and the fierce competence of nations such as China, the Emirate Arabs, or the European Union.