The U.S. Department of Justice sued on Wednesday to block the proposed merger between AT&T and T-Mobile -- a move that clouds the future of T-Mobile, serves a stimulus for antitrust lawyers and perhaps provides a preview of similar roadblocks to come from the FCC and the California Public Utilities Commission.

The Justice Department said it's opening to working out a deal with AT&T, but if that doesn't happen or it loses in court, the company would owe T-Mobile's German parent company more than $3 billion. But even that cash might not be enough to keep T-Mobile afloat because its German parent has refused to invest heavily in T-Mobile's operations.

The Justice Department said essentially it still hasn't seen AT&T make any arguments that the deal would benefit consumers. More at the Wall Street Journal.