SAN FRANCISCO — The Democratic National Committee on Saturday quashed a push from climate activists and some national party members who want a 2020 presidential primary debate devoted exclusively to the climate crisis. The national party committee voted 222-137 at its summer meeting in San Francisco against a resolution that effectively would have rolled back debate rules set by Chairman Tom Perez and freed presidential candidates to participate in a climate-only debate. The move drew rebukes from the Sunrise Movement and other activists who say the party leadership is ignoring young voters' priorities. "The Democratic Party needs the energy and...