What to know about the Senate worldwide threats hearing:  The Trump administration's spy chiefs will testify before the Senate Intelligence Committee on Wednesday at 10 a.m. on national security threats facing the U.S.  The officials testifying include the Director of National Intelligence Tulsi Gabbard, CIA Director John Ratcliffe, FBI Director Kash Patel, National Security Agency chief Lt. Gen. William Hartman and Defense Intelligence Agency Director Lt. Gen. James Adams.  The hearing will