Why mandatory? Every state has different laws pertaining to the amount of training, some only on written, and some have none.
There is no correlation at all, in studies, that shows states with mandatory training have fewer gun incidents than those with less training or no training. (there is one study between WA and OR, where WA with a higher population, a shall issue state, and no training requirements at all, has fewer gun incidents/accidents than OR which has fewer people, is a may issue state, and has training requirements. I dont have link to it anymore tho.)
And it's not something that has any bearing on crime at all.
Is the assumption that people just wont get training if they are not forced to? In some states, it costs people $200 or more to fulfill such requirements. A way to actively keep some people from cc permits.
If that is your assumption, why? And if no data supports it, why mandate it? (Again, with no data to support otherwise, the assumption IS that people get necessary training on their own, not that they dont get training.)