Its arms race with the U.S. was draining the country of funds , and further weakened by internal pressures , ethnic and political .
The Sino - Soviet split had removed the USSR 's most powerful ally , the People 's Republic of China .
USSR 's arms race with the U.S. was draining the country of funds , and further weakened by internal pressures , ethnic and political .
The Sino - Soviet split had removed the USSR 's most powerful ally , the People 's Republic of China .