To highlight that chapter of history is not to compete for the share of contribution to the WWII victory, but to remind the international community to attach equal importance to what China and Russia, and other anti-fascist allies, sacrificed during WWII.

World War II has now been consigned to the memory hole of history, especially in the United States. We live in a society where last week becomes ancient history, and where the ephemera of cheap insults tweeted and magnified through social media even drive national presidential campaigns.

But the past cannot be so easily banished from the present. Sigmund Freud taught us that the repression of important memories is lethally dangerous. It leads to subconscious drives to act out repressed events in compulsive, irrational and self-destructive forms of behavior.

What is true of individuals is also true of nations and national cultures that are composed of hundreds of millions of individuals. That is why the study of history, and the recovery of national as well as individual memory are crucial to preserve world peace.

Xi and Putin understand these profound truths. Obama, Cameron and Abe clearly do not. They refuse to acknowledge who really won World War II and who made by far the greatest sacrifices to save the entire human race from the worst barbarism in history. Such amazing ignorance and arrogance is repulsive. It is also highly dangerous. The only way to preserve world peace in this century is to remember and acknowledge the sacrifices that saved humanity 70 years ago.

The author is a senior fellow of the American University in Moscow.