Driving into Cleveland on a warm July Saturday to secure my press credentials for the Republican National Convention, I get a text from a friend in California, a guy in his thirties who knows what’s going on. He surfs the dark web. He gets how Bitcoin works. He’s a Mason, an actual Mason, in a lodge, and he loves to discuss the sort of trippy conspiracies that Masons were once accused of backing. Having learned from my Twitter feed that I’m in Ohio to cover the G.O.P.’s nomination of Donald J. Trump for president of the United States (does…