The right to bear arms

I have never really understood the American Constitution providing there to be a right to bear arms. Some Americans hold this right to be of great importance, but I do not understand why they feel this. I can understand there being a right to defend yourself, your property and others. A right of self defence always involves reasonableness (or as the European Union prefers to call it proportionality) and reasonableness. I cannot understand that there should be a right to bear arms.

I confess that I have never owned or fired a gun and although I live in London where very few would ever dream of bearing arms, I have travelled extensively throughout all parts of the United States and know that people do cherish the right to bear arms. They regard it as being in some way fundamental to retaining America’s freedom yet I am sure no one in the United Kingdom feels it necessary that we have to bear arms in order to defend our freedom.

When the right to bear arms became a constitutional right in the USA the arms that were in existence were daggers, swords, pistols and muskets. Since then rifles (which were not invented until 1850 or thereabouts, hand guns with revolving and cartridge chambers, machine guns hand grenades, mortars, bazookas and other devices have all been invented. Do the proponents of the right to bear arms think that they have a constitutional right to bear, for example, bazookas and hand grenades in defence of their democracy. Are small nuclear weapons and bombs included as part of the right to bear arms? I would love to know.