The defense-secretary nominee Mark Esper testifies before a Senate Armed Services Committee hearing on his nomination in Washington, D.C.Erin Scott / Reuters

If Mark Esper is confirmed as defense secretary—after seven months without anyone confirmed in that position—he will be walking into the same predicament many other Trump-administration officials occupy. Doing the job right requires speaking the truth. Keeping the job may require catering to a president with little use for it.

Democrats pressed Esper at his confirmation hearing today on whether he would stand up to President Donald Trump. The hearing kicked off with a nod to the last defense secretary, when Senator Tim Kaine introduced Esper and recalled his discouragement when the widely revered Jim Mattis resigned. “What we’ve hoped for,” Kaine said, “is a successor who can show the same level of candor and principle, and a willingness to remain independent even in the most challenging circumstances.”

Kaine said that he was convinced of Esper’s character and judgment after two years of working with him. Yet the whiff of nostalgia for Mattis was telling. Many saw Trump’s first defense secretary as a check on the president’s worst instincts. His deputy and successor, Patrick Shanahan, never achieved that reputation, and presented an affect that was more can-do than cautious when it came to the president. He declared the Pentagon not the “Department of No” but the “Department of Get Stuff Done.” Shanahan ultimately withdrew from consideration for the permanent post over revelations from his troubled divorce.

Esper served in the military and on Capitol Hill, and most recently was an executive at Raytheon, one of the U.S.’s largest defense contractors. In the tensest exchange of an otherwise tame and affectionate hearing, the presidential aspirant and Democratic Senator Elizabeth Warren repeatedly pressed him to recuse himself from decisions related to the company, and commit to waiting four years before joining another defense contractor after leaving government service. He refused, saying that the ethics safeguards he had in place were adequate.

Kathleen Hicks, the senior vice president at the Center for Strategic and International Studies and a former senior Pentagon official in the Obama administration, wrote in an email that Esper will also have to navigate changes in the Pentagon, shifting signals from the White House, and keeping the military apolitical. “The military has been used too often as a political backdrop, with virtually no one in the department’s leadership making it a priority to publicly set norms of apoliticization. Although many Americans are not closely following this issue, it’s clear to experts that such politicization runs the risk of creating instability in our democracy,” she wrote.

As for how he will deal with Trump, Benjamin Friedman, the policy director at Defense Priorities, an organization that advocates military restraint, wrote in an email: “He seems like someone another administration would nominate for a mid-level Pentagon job, not someone with the stature and guts to sway Trump to follow his realist instincts and buck the advice of his hawkish cabinet.” Esper, he wrote, does not have a lot of experience in the public eye.

To the extent Mattis himself managed to live up to the truth-to-power reputation of senators’ wistful yearnings, even he saw its limits. Insider accounts such as Bob Woodward’s book Fear detail examples where Mattis slow-rolled or ignored orders he felt unwise. Woodward writes, for instance, that after Syrian President Bashar al-Assad’s government killed dozens of civilians with chemical weapons in April 2017, Trump told Mattis, “Let’s fucking kill him,” in what seemed to be an assassination order. Mattis, by Woodward’s account, said he’d get right on it and then told an aide: “We’re not going to do any of that.” Mattis slow-rolled the military transgender ban Trump announced via tweet. But he also attracted criticism toward the end of his tenure for assenting to send U.S. troops to the border in support of Trump’s immigration policies.

He ultimately resigned after finding his advice on Syria ignored, and his personal assurances to allies violated, when the president abruptly announced last December, again via Twitter, that the United States would be withdrawing its troops from the country immediately. Trump ultimately reversed course, but it wasn’t Mattis who persuaded him (different accounts credit Senator Lindsey Graham, National Security Adviser John Bolton, or the retired general and TV personality Jack Keane). By the time Trump announced in February that he would leave a “residual force” in Syria, Mattis was gone, having explained himself this way in his resignation letter: “Because you have the right to have a Secretary of Defense whose views are better aligned with yours … I believe it is right for me to step down from my position.”

Gary Peters, a Michigan Democrat, read these lines aloud to Esper at the hearing. He noted Mattis’s emphasis on alliances and Trump’s skepticism of them. He asked whether Esper’s views aligned more with those of his boss or his predecessor.

Esper hesitated a bit. “I don’t know where to pick between the two, but clearly I shared Secretary Mattis’s views and I stated that publicly.”

Peters asked whether Esper was willing to resign if asked to support a policy that ran counter to his values. Esper responded: “Absolutely.” In a later exchange, he was asked whether he, like Mattis, would have resigned over the president’s abrupt withdrawal from Syria. He did not offer a view on the policy, but said he would offer his candid advice.

That’s a basic part of the job description, but Democratic senators in particular seemed to need the reassurance. Still, Esper is destined to fall short of what Trump’s biggest opponents, on the Hill or anywhere else, really want: not just someone who can stand up to Trump, but someone who can actually steer him away from his instincts. Mattis, despite the hopes placed in him, was not that person. Shanahan was not that person. Esper won’t be that person. It’s not his job. Donald Trump is the president.

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