A historic legal case in Maryland’s largest county is shining the spotlight on a rare intersection between rising antisemitism and gun restrictions.Montgomery County is Maryland’s most populous county and holds the largest Jewish population in the state. It is also where roughly two-thirds of all antisemitic incidents take place in Maryland, which ranks ninth nationally for antisemitic reports.That triggered the perfect setup for a clash in July, when the county passed a law criminalizing the carrying of a licensed firearm in or within 100 yards of “a place of public assembly,” which includes synagogues. The new regulation sparked uproar from...