Taylor Swift performs during the Eras Tour in London.Kate Green/Getty ImagesTaylor Swift officially endorsed Kamala Harris for president on Tuesday night.Her statement arrived amid a wave of criticism from fans who were disappointed by her silence.The impactful timing of Swift's endorsement shows the value of holding celebrities accountable.Last night, left-leaning Swifties everywhere breathed a sigh of relief: Taylor Swift finally endorsed Democratic candidate Kamala Harris for president.The Harris campaign seemed relieved too, if not ecstatic.