It is nice that that is written in the constitution of the US. But It's not written in the constitution of many many other countries.
That doesn't mean that in those countries you don't have a right to bear arms.
No human in the world needs permission, (from another human), or some scribbles on paper by some politician in the past,that then declared having a gun is legal or written down as an unalienable right, to bear arms.

Or to make it shorter. No one can say that I may not have a weapon to defend myself.