The "wouldn't have prevented" gambit on gun-safety laws

[spin]

12. I agree that all gun owners should be required to have safety training. ...

I also feel that they should have to show proof of such training in order to buy a firearm or ammunition.

Scuba divers have to present a card showing that they have been certified when booking a diving trip, renting equiptment or filling their tanks with air.

A Diving certification is a document (usually a wallet sized plastic card) recognizing that an individual authorized to do so, "certifies" that the bearer has completed a course of study as required by agency issuing the card. This is assumed to represent a defined level of ability and knowledge in scuba diving. Divers carry a qualification record or certification card ("C-card&quot which is required to prove their qualifications when booking a dive trip, hiring scuba equipment or filling diving cylinders. Although recreational certifications are issued by numerous different diver training agencies, the entry-level grade is not always comparable. Different agencies will have different entry-level requirements as well as different higher-level grades, but all are claimed to allow a diver to develop their skills and knowledge in achievable steps.[1][2]
http://en.wikipedia.org/wiki/Diving_certification