After Twitter was caught last month “shadow-banning” Republicans, while giving Democrats unrestricted voice, the social-media giant insisted it has no political agenda. But records of its political contributions show board members, top executives and major shareholders have all given overwhelmingly to Democrats, including Hillary Clinton and Barack Obama, while snubbing Republicans and Donald Trump. Federal records reveal 80 percent of Twitter’s corporate PAC contributions in the 2018 election cycle have gone to Democratic candidates, none of whom are moderates. Liberal Democrats also got top dollar in the 2016 race. The lobbying records I reviewed, moreover, show Twitter has sought to...