On the night of December 7th San Francisco’s Palace of Fine Arts, with its lakeside colonnade echoing a Roman ruin, turned into Mar-a-Lago, as Silicon Valley’s newly emboldened right-wingers gathered for a Christmas bash organised by the All-In podcast. The festive good cheer did not extend to everyone; The Economist was made to feel most unwelcome. But not before being privy to a riotous celebration of how a clique of billionaires—the…