There's increasing evidence that Ukraine has seized momentum in the six month old war.

On October 8, a blast crippled the Kerch Strait Bridge, which links the occupied Crimean peninsula to Russia.

Now, Russia is responding by sending missiles into Ukrainian cities in what it calls revenge attacks.

Today on Please Explain, digital foreign editor Chris Zappone joins Nick O'Malley to discuss the latest attacks, and whether the Russian setbacks will see Vladimir Putin turn to nuclear weapons.