Is it important for textbooks about the history of the Soviet Union to emphasize military strength?

Yes. It is important.

Explanation:

The history of the Soviet Union's military started following the October revolution that brought Bolsheviks to power. The new government formed the Red Army in 1918. The Red Army defeated several internal enemies, Poland, Estonia, Latvia and Finland. In world war two, they played a huge role in conquering the Germans. Following the victory, the Soviet Union became the major superpower rival to the United States. By early 1980s, the Soviet armed forces had more ground troops, nuclear weapons and artillery guns than any other country on earth. The political and economic chaos of the late 1980s led to the collapse of the Soviet Union.

The Soviet Union's military power and the role they played in world war two, is a significant part of their identity and history and therefore should be emphasized.