>>Presidentâs canât change laws.
He can have his alphabet agencies change regulations, interpretations, and forms. Imagine a $200 NICS fee, the addition of the no-fly question to a 4473 (and to the NICS), reinterpretations of what constitutes a straw purchase, restrictions on sales of guns at any place of business (i.e. parking lots or gun shows) without an FFL, or changes to questions 11e or 11j to include legal drugs or anti-government statements.
He can do none of those things.