Well DGF, given the ramifications that the Gov. of WI. is calling State Troopers to maintain order at the fair, and the targets of the mob were white, these are mitigating factors should you find yourself in a similar threat.
One cannot be afraid of legal ramifications, when your life in is in imminent peril. As you are a Veteran, an older and wiser gentleman, a family man, and found yourself approached by a gang of thugs, hell bent on injury, (the superficial nature of the injuries, I will not bet my life on), regardless of their age, those will work against the punks...and most likely get you a pro bono lawyer from the SAF.
Virginia as I recall, as a former Fairfax County Resident, does remain a pro-gun, state.
"Arms in the hands of citizens (may) be used at individual discretion...in private self defense..."
John Adams, A defense of the Constitutions of the Government of the USA, 471 (1788).
All the best, and thank you for your service.
tw