The article says "license to buy" not "license to own." I know that in Minnesota you need a Permit to Purchase from your local PD or a Permit to Carry from your local Sheriff in order to purchase an AR-15 (or a handgun).
The majority of US states have no such requirement. In VA I can purchase a gun from another VA resident with no paperwork; I can purchase from a dealer by filling out a one page form with name, DOB, address, and place of birth.
You can do that for long rifles in MN as well (although I think you forgot the NICS check required for all gun purchases regardless of state). It's just hand guns and "black" rifles that require the permit. VA obviously has a more enlightened view than MN (IMO).
