HSBC, Citigroup and the End of Global Banking

(Bloomberg Opinion) — Twenty years ago, as they returned from summer vacations, staff at HSBC Holdings Plc began moving into their gleaming new global headquarters in London’s Canary Wharf. Designed by Norman Foster, the building was one of two new towers to spring up on the skyline east of the City. The other was home to Citigroup Inc., whose employees had moved in a few months earlier. At the time, these were jointly the second-ta…