"The second Syria Principals Committee meeting convened at one thirty and again consisted largely of the various agencies reporting on their developing planning and activity, all consistent with a strong response. I soon realized Mattis was our biggest problem. He hadn't produced any targeting options for the NSC or for White House Counsel Don McGahn, who needed to write an opinion on the legality of whatever Trump ultimately decided. From long, unhappy experience, I knew what was going on here. Mattis knew where he wanted Trump to come out militarily, and he also knew that the way to maximize t he likelihood of his view's prevailing was to deny information to others who had a legitimate right to weigh in. It was simple truth that not presenting options until the last minute, making sure that those options were rigged in the "right" direction, and then table-pounding, delaying, and obfuscating as long as possible were the tactics by which a savvy bureaucrat like Mattis could get his way. The Principals Meeting ended inconclusively, although Mattis gave some ground to McGahn in the end after a little temper-flaring around the Sit Room table. I was determined that this obstructionism would not happen, but Mattis had clearly dug in. I didn't think he was over the line yet, but he was right on it, as I said to both Pence and Kelly after the meeting."