The two men armed themselves, as is their right, in order to defend themselves........
Maybe it's just me but I would think it would be difficult to convince a jury you were defending yourself when you were armed and in a truck, pursuing an unarmed guy on foot.
If you carry CCW, as many here do, then you are arming yourself while interacting with unarmed people every day. Why? Isn't it in order to defend yourself should someone bring unlawful violence your way? This is why these two men armed themselves, too. In fact, it was more likely they'd need to arm themselves for self-defense while attempting to make an arrest of a burglar than it is likely that you would need to arm yourself in order to make a run to the store for some milk.
