Final answer:
The arms race contributed to Cold War hostilities by fueling a race to acquire nuclear weapons and improve missile capabilities. It also indirectly led to the space race and involved competing for influence in other nations.
Step-by-step explanation:
The arms race contributed to Cold War hostilities through a combination of factors. Both the United States and the Soviet Union invested significant amounts of money in building powerful militaries, which included the development of nuclear weapons. The race to acquire nuclear technology and improve missile capabilities indirectly led to the space race between the two superpowers. Additionally, the arms race involved competing for influence in other nations and engaging in proxy wars.