Eye for an eye. Or better yet two eyes. Escalate boldly and actively till the bully backs off and maybe a bit more to make sure he's not faking.
Alas, I still don't have a single tank to my name, so it's not me that will be doing the shooting. Or even deciding to shoot.
At 45 years I already lived too long and seen too much. I don't mind universe giving me its best shot at mythical thermonuclear war. I fully expect it to be pathetic.