The $2 million fine that the Treasury Department levied on Exxon Mobil this week for violating sanctions against Russia is just a sliver of the oil company’s $7.8 billion in profit last year. But Exxon has decided nonetheless to wage a legal battle — one that could make President Trump’s cabinet meetings decidedly awkward. Rex W. Tillerson , now the secretary of state, was Exxon’s chief executive at the time of the actions in dispute in 2014. And his former company is suing the Treasury and Steven Mnuchin, the Treasury secretary, in hopes of getting the penalty withdrawn and its reputation cleared. The clash has created a new wrinkle in the intrigue that has captivated Mr. Trump’s Washington, and it has left some wondering why Exxon would fight over a paltry sum as a political furor over Russia swirls. “It’s a fascinating dynamic playing itself out,” said […]