You must know something about questions we are going to pursue, and think about why they are important. There are certainly many more important questions (or there wouldn't be so many historians), some of them as important (or more so) as these:
1. Who or what is in charge? Not just individuals responsible, but forces, institutions, etc. This also means grappling with the issue of who exactly is in charge? How broad is the power that is responsible? Is there an elite? What is nature of that elite? How much role do ordinary people play? If there is such an elite, is there any central mission of this elite? What do they want to achieve? What did they achieve? What did they produce?
2. What kind of world or system have policymakers and others imagined (what kind of questions do we need to answer to answer this one?) at crucial turning points?
3. Has American Power been good or bad for the rest of the world? How do we assess this?
4. Is the U.S. an empire? If so, what kind? If not, how do we describe the nature of U.S. power?
5. Why did the United States Enter World War I, II and other wars?
6. Why the Fear of Communists and other radicals?
7. Who or what started the Cold War? How central should the Cold War be in our narrative of post-1945 international history?
8. Why and how has the US keep interfering in other people's struggles and intervening around the world?
9. What did the Cold War do to us?
10. Why did September 11th happen? What was its meaning for the US and its role in the world?