Mark Milley, the retired U.S. Army general and former chairman of the joint chiefs of staff, worries that Donald Trump will order a military trial against him if re-elected, according to a new book. Veteran journalist Bob Woodward reveals in his new book, “War,” that Milley recently “warned former colleagues that Trump intends to recall and then court martial retired senior officers who have criticized him as part of a wide-ranging revenge campaign he has pledged to carry out in a possible second term as president, according to excerpts published by The Guardian. “He is a walking, talking adve…