Taking the Scots to Heart
The Scottish, gotta love them because I'm one of them. How's this for a motto? NEMO ME IMPUNE LACESSIT which translates into something like, none may harm me with inpunity or attack me at your peril.

Which is a pretty good philosophy for life, I can also interpret it this way: leave me be and I'll likely leave you be, but any attack will be met with ever greater retaliatory action.