Firearms and edged weapons aside, and there are many, if not most, times that they are exactly that, left at home or out of reach, the best defense one has is a situational awareness, and control of movement, posture and attitude.
On the street your gate (
way of walking) and attention level is paramount. Being aware of what's going on around you and paying attention to your surroundings is more important than what you are carrying.
Street criminals are like Jackals, they seek out the weak, or the oblivious. If confronted make hard eye contact and act like you are carrying even if you aren't. Don't be confrontational, but be firm, the goal is to walk away, not bag a couple of street punks.
Of course there are places where this only gives them a chance to get the first shot off, so your milage may vary ... There are places that you should just
not go, at least that's the way it is here. Like tying off to a rotted limb, best advised just not to go there.
I'll talk my way out if I can, walk my way out if I can, and even run like hell if I have to avoid either getting cut or shot, or nearly equally, having to cut or shoot. I'd much rather cut out than shoot out.
Truth is, I rarely carry anything other than my money clip as on offensive weapon:
Aerial