It probable refers to WW2 as the conflict between two countries started then, mostly because of the division of the influence in the post-war world, although it all started with the division of Germany.
Explanation:
After WW2 two countries were seen as strongest military and economical powers in the world. Still, two opposite ideology led to confrontation between the countries. Peace treaties and division of influence in the post-war world made these two countries enemies practically in the whole world. Both countries supported governments of other countries, so they could achieve more influence on a global scale.
