AT&T, Charter, Comcast and Verizon are quietly trying to weaken a $42.5 billion federal program to improve internet access across the nation, aiming to block strict new rules that would require them to lower their poorest customers’ monthly bills in exchange for a share of the federal aid.In state after state, the telecom firms have blasted the proposed price cuts as illegal — forcing regulators in California, New York, South Carolina, Tennessee, Virginia and elsewhere to rethink, scale back or ...