Announcing Shanahan’s withdrawal, President Donald Trump said in a pair of tweets that the former Boeing executive had decided to “devote more time to his family,” thanked him for his “outstanding service” and announced that Army Secretary Mark Esper would now serve as acting secretary of defense. The announcement came with no formal nomination of Esper for the post, meaning the Defense Department remains without a permanent head even as the United States faces a growing confrontation with Iran and dispatches more troops to the Middle East.
Shanahan, who previously served as deputy to then–Defense Secretary James Mattis, took over the department after Mattis abruptly resigned when Trump announced that he would pull all U.S. troops out of Syria, over Mattis’s objections. Trump ultimately agreed to leave a residual force of a few hundred troops there, but in the meantime, Shanahan’s efforts to defend the withdrawal earned him early skepticism from lawmakers. Senator Lindsey Graham, for one, told reporters that he had told Shanahan if the plan to completely withdraw were carried out, “I am now your adversary, not your friend.”
He faced skepticism or outright trouble, too, for Trump initiatives such as military funding of a border wall and the creation of a “space force,” the latter of which several lawmakers said would create unnecessary and expensive bureaucracy. In contrast to Mattis, who had a reputation as a warrior-intellectual, Shanahan seemed to struggle when answering questions in congressional hearings. Also unlike Mattis, he had no background to speak of in foreign-policy or defense affairs.
It took Trump a full five months to announce that he intended to nominate Shanahan to fill the role, much to the relief of Senate lawmakers who were growing impatient to have a permanent defense secretary. Trump’s hesitation reportedly stemmed in part from Shanahan’s three-decade career at Boeing, which was then dominating the headlines over two separate crashes of its 737 Max 8 plane. (Shanahan worked on a different program while at Boeing, but his reported reputation in Trump’s eyes as “the Boeing guy” complicated his prospects.)
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Yet a month after Trump said Shanahan was his pick, he still hadn’t sent his nomination to Congress. Reports surfaced that Trump might have been souring on his pick and looking for alternatives—others suggested that paperwork was to blame.
In the end, though, it was a harrowing personal story that made Shanahan’s continued service untenable. The Washington Post reported that his wife had punched him and that his son had beaten her with a baseball bat; his wife told police that Shanahan had punched her in the stomach, though he denied that. Shanahan’s statement said: “I would welcome the opportunity to be Secretary of Defense, but not at the expense of being a good father.”