AT&T has undergone several major strategic shifts since its big 1984 break-up, but it continues to shape-shift. The latest episode in its saga is to divest a series of media and content businesses it had acquired in a bid to move up the value chain and become a significant content provider. Moving back to the core broadband businesses may look like a volte-face, but it is no more dramatic than the twists and turns of AT&T’s long history. The 1984 break-up turned it into a long-distance provider, losing its local operations which were divested into seven RBOCs (Regional Bell Operating Companies), dubbed ‘Baby Bells’. AT&T had dominated US local and long-distance telephony throughout the 20th century and skirmished with regulators…