In every election supporters – voters – of the winning side shout, blow their horns, ring cowbells and light firecrackers. That happened in La Conner as well as around the country Saturday morning with the news that Pennsylvania had been called for former Vice President Joe Biden. He will become the nation’s 46th president. Kamala Harris joins him as vice president with a string of firsts: as a woman, an African American and of south Asian heritage, a child of immigrants.

Their victory is substantial and will have a larger margin by the time the state of Washington certifies i...