Trump's new defense chief's history as a Boeing executive is raising concerns, but he's not the only one with deep military-industrial ties

Patrick Shanahan arrived at the Pentagon in July 2017 with more than 30 years of experience at Boeing.

It's not unusual for defense officials to have worked for private-sector defense firms for part of their career. But Shanahan's three decades at one of the largest defense contractors attracted scrutiny. The late Sen. John McCain, who chaired the Senate Armed Services Committee, expressed concern about an executive from one of the five firms that account for most of US defense spending taking a senior Pentagon post.

"I have to have confidence that the fox is not going to be put back into the henhouse," McCain said during Shanahan's confirmation hearing.

This month, as Shanahan took over the top Pentagon job after Jim Mattis' acrimonious departure, he said he would recuse himself from matters involving Boeing for the "duration of his service in the Department of Defense."

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But some accounts indicate he's rooting for his old team. According to a recent Politico report, in 18 months at the Pentagon, Shanahan has been heard to boost Boeing and trash its competitors, including Lockheed Martin, which Shanahan reportedly said "doesn't know how to run a program," referring to the F-35 program, which he reportedly called "f----- up."

While Shanahan spent his career with a defense contractor, other officials leading the Office of the Secretary of Defense have mixed backgrounds.

Ellen Lord, the head of acquisitions, spent nearly 15 years with Textron, another defense firm, before joining the Pentagon. John Rood, head of policy, worked in government for nearly 20 years before spending 10 years in the private sector. Joseph Kernan, the head of intelligence, spent his career in the Navy before retiring in 2013.

Below, you can see the backgrounds of the leadership in the defense chief's main staff office, responsible for developing policy, managing resources, and evaluating programs.

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