Passengers at airports in Pennsylvania and British Columbia were stunned Tuesday when loudspeakers suddenly blasted pro-Hamas messages and slurs against President Trump and Israeli Prime Minister Benjamin Netanyahu. Videos posted by travelers showed the unauthorized recordings echoing through terminals at Harrisburg International Airport in Pennsylvania and Kelowna International Airport in Canada. Screens at Kelowna also flashed messages praising Hamas and calling for “Free Palestine,” according to officials and witnesses. Airport authorities said the digital break-ins targeted both public address systems and flight information displays — a form of cyber-vandalism that disrupted boarding and startled passengers but caused no flight safety...