(Bloomberg) -- Major US cities are tightening security after President Donald Trump unleashed airstrikes on Iran, a direct military intervention that’s deepened Washington’s role in Israel’s war with Tehran and raised concerns about potential retaliation.Most Read from BloombergBezos Wedding Draws Protests, Soul-Searching Over Tourism in VeniceOne Architect’s Quest to Save Mumbai’s Heritage From DisappearingJFK AirTrain Cuts Fares 50% This Summer to Lure Riders Off RoadsNYC Congestion Toll Cuts