Since enforcing background checks on all gun purchases is difficult, another approach is to require a hunting/gun license to buy ammunition and to require a background check to get a hunting/gun license, or to simply require background checks and ID to buy ammunition.
Why is this important?
We need to find new ways to improve public safety and take reasonable measures to keep people who should not have easy access to weapons from doing so. Targeting the sale of ammunition is another point at which safety measures may be enforced.
