This successful but discreet persuasion campaign offers a rare glimpse into how corporate America can still bend Trump’s ear. Trump’s policy positions are notoriously elastic (see: “TACO trade theory”), but his personal vendettas — think Fed Gov. Lisa Cook or James Comey — tend to be one-way ratchets. Yet a crew of Silicon Valley heavyweights managed to engineer a presidential walk-back — directly, not just through strategic appearances on Maria Bartiromo.It suggests a barely-perceptible-but-the...