There is -- as far as I'm aware -- no good data to suggest any of this is true. The severity of punishment has no correlative link let alone causative link to crime rate. As for "politeness" I don't even know how to tackle this, I know Japan and Canada are considered "polite" by public opinion and both have stricter gun regulation than US. And as for the great equalizer claim while I can see that theoretically it could be an equalizer of force that would only be the case if the "weak" were as likely to have a gun as the "strong". If we simply compare women to men -- since women are often physically weaker than men -- we see the gun ownership rates skew heavily towards men. So if anything in that context not only is it not equalizing it is further dividing the gap between the weak and the strong in this context.

Guns don't create a more polite society, they create a more fearful society.

Polite isn't the same as fear. Also both your catchphrases are right wing NRA bullshit propaganda which isn't remotely true.