Trapping a Russian armored column

Fabulous videos on the Wall Street Journal show that Ukrainian troops have lost none of their ingenuity in ambushing the enemy, much as the Finns did in 1939-1940: Let the Russians advance in line, knock out the leader, disable tail-end Charlie, and destroy the rest at leisure. (Scan down the page to see the second strike, by a drone.) The war may be stalemated, but it's no less costly for the invaders.