I am a European. I cannot understand why Americans want to have so many people owning guns
There was a point in our American History where the government tried to repress dissidents in its population. They did this through search and seizure without due process, and wanton murder of its citizens. Those citizens eventually overthrew the tyranny of that government. If those citizens had been refused the right to bear arms they would have been massacred and we would have a picture of the queen in every bar.
So in answer to your question... we keep the right to bear arms because we remember far too well what it is like to live under a government that may turn on its citizens.
Today our arms are less in the form of flint and powder and more in the terms of primes and curves. In the end it is all the same. A government may claim it is abolishing guns to save the innocent, but the symbolism of that in our history runs far far deeper than that. On the same note a government may repress a citizens rights to cryptography because enemies use secrets, and secrets are bad, but at the same time preventing secrecy only serves to make that government more powerful.
So, in a civilized society do we need guns... No.
In a civilized society do we need secrets... No.
Sad part is... our society is not civilized, and often some of the least civilized are in positions of power.
So you can take my guns... but if that right is ceded, it is only a matter of time before you take my crypto-kit too.
The truly sad part is... I thought, more than twice, of the wisdom of publicly publishing these views knowing all too well, that in the country in which I live, they can very well be used against me.