““In the end this is a human process,” said Leon Panetta, who served as defense secretary and CIA director for President Barack Obama. “What human beings tend to do is they make judgments about people who are at the table, and whether or not they have the strength and the position and the knowledge and the experience to be able to voice their opinions.” 

https://www.washingtonpost.com/world/national-security/trumps-decision-making-on-iran-strike-highlights-absence-of-a-confirmed-defense-secretary/2019/06/22/6f617d8c-950e-11e9-b72d-d56510fa753e_story.html