You do have a point, the British weren't prepared for guerilla warfare. But I don't think it necessarily carries over to the modern day, our military's at least got some experience in urban warfare and the like. It probably depends a great deal on how far the government's willing to go and how far the military's willing to go.
I understand the principle and I respect it. I just really, personally and at a visceral level hate the idea of armed uprising. I want the system to be salvageable. I want dialogue and compromise. But I suppose if it came down to real, true tyranny then you'd be correct. Everyone has the right to stand against that.