The FBI briefed the Senate yesterday and today on the progress in the Boston Marathon bombing case, but more questions than answers may have arisen from it. The Boston Globe quotes multiple sources from within the briefing that the FBI didn’t just get one warning from Russia about Tamerlan Tsarnaev, they got warned repeatedly — including after the FBI’s initial investigation of the now-deceased bomber: Russian authorities contacted the US government with concerns about Tamerlan Tsarnaev not once but “multiple’’ times, including an alert it sent after he was first investigated by FBI agents in Boston, raising new questions about...