Ever since Russian President Vladimir Putin ordered his attack on Ukraine last year, the West has faced a conundrum: How do you support Ukraine in its heroic self-defense without tripping over Putin’s "red lines” and ending up with Russia and NATO shooting at each other directly?

Put differently: How do you help Ukraine win without starting World War III?

This week, the U.S., Germany and France took a big step forward in probing that evolving question. All three announced that they’d give the Ukrainians new kinds of tanks. The Americans will send armored fighting vehicles called Bradleys. The Germans will supply their equivalent, called Marders (German for martens). The French will ship similar vehicles, called AMX-10s.