Economic failures and years of warfare, the Chernobyl disaster, perestroika glasnost and Mikhail Gorbachev all of these factors contributed to the collapse of the Soviet Union or USSR in the year 1991. Some of these incidents had a direct impact on the breaking of USSR into several countries, while others had a direct role.
One important advantage that primary soruces have over secondary sources is that primary sources offer a firsthand account of an event - b, which isn't the case with secondary sources. Although this leaves primary sources prone to being biased compared to secondary sources.
Answer:
Japanese Americans on the West Coast were sent to internment camps without ever being accused of a crime.