1. No, not under the current conditions. But under conditions where there was a total collapse of central government it might be possible. Hopefully we would revert to each state becoming the central government in the absence of a national government. So, I could see where we may have periods of anarchy which would require so form of continual personal defense.
2. No, political opportunists maybe, but I think they are one in the same.
3. Change in the current system is, has, and will be very very difficult. Until we have a strong third party rise up and become so popular as to overwhelm the current electoral process with mass elections, things will plod along as usual. A third party could also make slow in-roads to the current process but who knows.