BOSTON (AP) — Anti-vaccine activist Robert F. Kennedy Jr. launched his longshot bid to challenge President Joe Biden for the Democratic nomination next year. Kennedy, a member of one of the country’s most famous political families who has in recent years been linked to some far-right figures, kicked off his campaign in Boston on Wednesday and likened his campaign to the American revolution. “My mission over the next 18 months of this campaign and throughout my presidency will be to end the corrupt merger of state and corporate power that is threatening now to impose a new kind of corporate...