I believe that it is my responsibility, as a US citizen, to be proficient in the operation and maintenance of a range of current US military personal arms. 250 years ago, this would have meant black powder weapons and perhaps a sword. Today, it means the anything from the M16A2, M-4 carbine, M-1014 shotgun, M-9 pistol, etc.
Owning weapons such as these makes living up to my Constitutional responsibility possible. Should the need arise for me to defend my home, my neighborhood, hometown, state or country, individual weapons training should not be necessary. Of course, I'll gladly accept ammo and spares on the taxpayers' dime.
"How old would you be if you didn't know how old you was?"
- Satchel Paige