Carlos Barria / Reuters

Why did Donald Trump, who won the GOP nomination, in part, by bucking his party’s interventionist foreign policy establishment, thrill it on Friday by launching missile strikes against the government of Bashar Assad? Why did the most unconventional of presidents respond to his first foreign policy crisis in such a conventional way?

The recent history of American foreign policy shows why it’s not that big a surprise. Even unconventional presidents tend to surround themselves with conventional advisors. Presidential candidates often promise to rethink the foreign policy assumptions that guided their predecessor. But as governors, senators or real estate developers, they generally lack experience in making foreign policy themselves. So they seek advisors familiar with America’s military and intelligence bureaucracies, and with foreign governments. And those advisors often espouse the very establishment assumptions their boss derided on the campaign trail.

Jimmy Carter didn’t want to be a cold war president. He vowed to overcome the “inordinate fear of Communism” that had led his predecessors to embrace brutal dictators and fight an unwinnable war in Vietnam. But in looking for advisors who possessed the foreign policy credentials he lacked, he chose Robert McNamara’s former Pentagon deputy, Cyrus Vance, and Zbigniew Brzezinski, a hawk he had met at the Trilateral Commission. By early 1978, Brzezinski was pushing him to send an America armada to the Red Sea in response to Ethiopia’s Soviet-backed invasion of Somalia, exactly the kind of cold war intervention Carter had sworn to avoid.

Like Carter, Barack Obama ran against the hawkish, bipartisan mindset that had led America into a disastrous war. Upon taking office, however, he didn’t give his top national security jobs to campaign advisors like Samantha Power, Susan Rice and Gregory Craig. He instead chose James Jones, a marine general with ties to John McCain, Bush administration holdover Robert Gates and Hillary Clinton. None had opposed the Iraq War. But they enjoyed credibility with the military, Congress, and America’s allies. During Obama’s first major foreign policy decision, whether to send additional troops to Afghanistan, Gates and Clinton urged him to escalate the war.

Establishment advisors often wield their greatest influence at the beginning of administrations, when new presidents lack the self-confidence to overrule them. In his first months in office, John F. Kennedy assented to a CIA and military plot to invade Cuba. It was only after that plot ended in disaster that Kennedy grew more willing to challenge their hawkish assumptions. “If it hadn’t been for the Bay of Pigs,” Robert Kennedy observed, “we would have sent troops into Laos.” Kennedy’s disillusionment also shaped his refusal to launch a preventive strike during the Cuban Missile Crisis.

Barack Obama’s about-face on Syrian military action in 2013 stemmed in part from a similar disillusionment. Jeffrey Goldberg has reported that during his fateful South Lawn walk with Chief of Staff Dennis McDonough, Obama expressed frustration that “the Pentagon”—led by Gates and aided by Clinton—“had ‘jammed’ him on a troop surge for Afghanistan.” He felt his advisors had also pushed him into an ill-fated military action in Libya. “Now, on Syria, he was beginning to feel jammed again.” Five years into his presidency, Obama possessed the self-confidence to buck what he called “The overwhelming weight of conventional wisdom and the machinery of our national-security apparatus.”

Now, in his decision to strike Syria, Trump is reverting to the pattern from which Obama broke free. Trump’s first national security advisor, Michael Flynn, was someone he had bonded with during the campaign and who shared some of his unconventional, pro-Putin, anti-Muslim, views. But Flynn’s outsider status estranged him from the national security bureaucracy he had to manage, and contributed to his ouster. So on Thursday night at Mar a Lago, Trump mulled the biggest foreign policy decision of his young presidency alongside a Secretary of Defense, a Secretary of State and a National Security Advisor who did not advise him during campaign and have no stake in the pro-Assad, anti-interventionist statements he made during it.

Trump’s alt-right base feels betrayed. So did the “Netroots” Democrats who had supported Obama against Hillary Clinton in 2008 because he had opposed the Iraq war. That’s no surprise. Ironically, the presidents most able to buck America’s hawkish national security establishment—the best example is Dwight Eisenhower, who ended the Korean War and for eight years at the Cold War’s height resisted fierce pressures to boost defense spending and send US troops to fight communist insurgencies in the developing world—are those who know that establishment best, and enjoy the prestige to take it on.

Neophytes, at least early on, generally get rolled.

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