Never touch it without gloves on, put it in a ziplock to keep it that way until needed.
Worked for the cops for years...
... it would also be a good idea to purchase a cheap folding knife...
No need to do that. The threshold for use of deadly force in self defense in most, if not all states, is reasonable fear of imminent death or great bodily harm. Or, in defense of others with the same criteria.
The all out assault by the 5 men described here would rise to that level.