If the government doesn't trust it's citizens to own firearms, why
should the citizens of a nation trust a government not to impose a
tyranny on them? Republican institutions of free men are based upon
the premise that it's citizens are rational such that they can be
trusted to possess fire arms to protect themselves, their communities,
and the nation, itself. In England, at one time, there was a
requirement that all freemen possess and train in the use of arms. I
believe that it was called the Assize of arms (or words of that sort).
If an English King trusts his subjects so much as that he orders them
to possess and train arms, then only a tyrannical form of government
would oppose them!