Blackened and bombed-out apartment towers. Families huddled together in subway stations. Downtown streets made silent, with shuttered cafes and nightclubs.

The images emerging from Russia’s invasion of Ukraine are reminders of what wars often prove: Cities are both key strategic targets and the places that bear the greatest costs of conflict.

Towns and villages in the path of the Russian advance have also been devastated. But it is the cities, which were home to about two-thirds of Ukraine’s population of 44 million people before the invasion, that are the focus of the Russian assault.