John Feinblatt, president of the Everytown for Gun Safety advocacy group, pointed out that mass killings in recent years prompted legislators on both sides of the aisle to bolster gun laws, such as when Florida raised the minimum age to buy rifles from 18 to 21 after Parkland. Robert Spitzer, adjunct professor at the College of William and Mary School of Law and the author of six books on gun policy, said he expects laxer ATF enforcement under Trump and the reversal of restrictions on ghost guns and at gun shows, saying those moves will eventually have “adverse consequences.’’ The 2012 slaughter of 20 young children and six staff members at Sandy Hook Elementary School in Newtown, Connecticut, was thought to be the turning point in the long-running clash between gun safety and gun rights…