Guardian: BP executives entered the White House for their hour of reckoning with Barack Obama today, 58 days after the explosion in the Gulf put the future of the oil company and the president in peril. The stakes of the meeting with the BP chairman, Carl-Henric Svanberg, chief executive, Tony Hayward, and two other company officials are high for Obama after the near-universal panning of his Oval Office address on the crisis last night. The outcome is equally critical to BP. Television …