Why is the world revolutionized? It is noteworthy that conflicts are increasingly rooted in economics and politics. Although these will continue to play a role, the cultural issue is growing. Now it should be said, imitating Clinton: "It's culture, stupid!"

We thought that the twentieth century had been the shortest (1918-1989) and that we had entered the twenty-first. But it seems that the Cold War continues, which would not have ended with the end of the USSR (1991). Culture would be among its causes. Most social fractures have this component, not just the socio-economic one: American Trumpism, British Brexit, French unrest, and now the most serious conflict, the Russian invasion of Ukraine.

Russia and Ukraine are independent countries, but brothers. Putin is named after Prince Vladimir the Great, who introduced the Orthodox religion to Slavic lands from Kyiv. In Russia there is talk again of Holy Russia, but Ukraine had been Mother Russia before. Because Putin's country has its origins in the medieval Russian of Kyiv, the first great gathering of Slavic tribes. Ukraine fell under the yoke of the tsars in the 18th century and then under the Bolsheviks in the 20th. Ukraine has been Russified, although it has been independent since 1991. But Russia was in the Middle Ages in Ukraine. An anecdote: Listen to the fiery Second Tchaikovsky Russian Symphony. It's called Little Russia. But this is Ukraine, where the musician of Ukrainian descent composed it in 1872. Or listen to the end of the paintings in an exhibition by his contemporary Mussorgsky: The Great Gate of Kyiv. Ukraine, in the best Russian music.

Putin wants to control the plains around the Dnieper. It is its western flank, from the Baltic to the Black Sea. He has invaded Ukraine, but he also wants to teach it. Zelensky speaks Russian, just like him. It is not a civil war, but it is a fratricidal war within a large historical community of ethnicity, religion, language and trade. With this ferocity, Russia is killing its comrades-in-arms.