The silk road spread from the Roman empire all the way to China for trade so it helped with expansion
The Classical Era set the scene. It brought us the major civilizations, religions, and trade routes. But, what happens when all of the major world powers collapse? This is the Post-Classical era. The major world powers come from places you might not expect. There are some powers that are similar to the ones before and the ones after (Byzantine, China). But, the major players in the Post-Classical era come from totally backwards places. One sprouts out of a cave in the Arabian desert. The other comes from the base of a mountain on the steppes in Central Asia. I call this era, Muslims & Mongols. That's not everything, but it just about sums up the basics. (Of course, Trade, Migrations, Religion, and Labor are important...) The Post Classical Era is the FIRST era that represents 20% of the test. From here on out, these eras are worth more than the first two.
Answer:
Kennedy worried that actions on the part of the United States might start a war with the Soviets.
Explanation:
The Cold War was a difficult period in human history, which every action could lead to a physical conflict. All the diplomacy would be taken carefully. The Berlin Wall was an East German initiative that was under Soviet control. Because of that, Kennedy was afraid that his actions were seen as a threat to the Soviet government, leading to a real conflict.