The skeptic who could shape Kamala Harris’s foreign policy

Harris staunchly backed President Biden, believing it was time to end America’s mission. But Phil Gordon advised caution. While the U.S. had failed to seed a democracy in Afghanistan, a small residual force could keep the Taliban at bay, he argued, preserving rights for women and avoiding a refugee crisis. There were also hard-nosed reasons to stay, Gordon suggested, such as countering local terrorist organizations threatening the U.S. and its allies.

Harris ultimately sided with Biden’s pullout, according to current and former officials who recounted the episode, a decision she reiterated Monday was “courageous" and “right." Gordon, despite his misgivings, fell in line behind his boss and the president.

The disagreement, which hasn’t been previously reported, provides greater insight into a relationship that could come to define the next administration—and global politics.

Gordon, now the vice president’s top national security adviser, could easily find himself in the same role to the president if Harris wins the election in November. It is unclear whether Gordon wants the coveted role, and he studiously avoids the issue when asked about it by aides or friends.

But the possibility of him serving in a senior job during a Harris administration has invited new scrutiny of Gordon’s record in the past three Democratic administrations, particularly since he would counsel a president with limited foreign policy experience.

If he is appointed national security adviser next year, the 61-year-old Europe and Middle East specialist could hold outsize influence, becoming both the architect of the new administration’s doctrine and the key executor of foreign policy decisions.

Interviews with current and former U.S. officials, many of them close associates, and foreign diplomats make clear Gordon believes in principles that are core to the Washington playbook: working with allies, defending sovereignty, ensuring the free flow of capital—even dropping bombs to protect human rights. But he is also increasingly a critic of establishment foreign policy thinking, having watched from the front row as the U.S. repeatedly failed to build democracies by force or persuade enemies to make deals via willpower alone.

“He’s a liberal internationalist who’s somewhat more skeptical than he was previously," said Steven Cook, a Middle East expert who worked with Gordon at the Council on Foreign Relations.

Gordon’s impact can already be felt in the way the vice president speaks about the war in Gaza. During her address to the Democratic National Convention last week, Harris vowed to support Israel’s right to defend itself while “at the same time" pushing for an end to the conflict that has devastated Palestinians. The use of that particular phrase to transition between thoughts—rather than “but"—allowed Harris to express how she holds two seemingly competing ideas at once.

Frank Lowenstein, who aimed to broker peace between Israelis and Palestinians alongside Gordon during the Obama years, had an immediate reaction upon hearing Harris’s remarks: “This is classic Phil."

A common refrain is that Gordon is a pragmatist, willing to go where the facts take him. That reputation stems from his time leading the Middle East portfolio in the Obama White House, as he saw U.S.-backed efforts to topple Syria’s Bashar al-Assad falter once Russia entered the fray and terrorists like Islamic State filled the vacuum.

Starting in late 2013, Gordon expressed pessimism that the U.S. could compel Assad to step down. A former official said Gordon often stuck his neck out in the Situation Room, offering others ideas like the pursuit of localized cease-fires and a decentralization of governance that, over time, would delegitimize Assad’s regime.

His suggestions received fierce pushback at the time from Secretary of State John Kerry and Samantha Power, the U.S. ambassador to the United Nations. “There was definitely some friction," the former official continued, noting the top leaders argued the U.S. should continue backing the Syrian opposition who, with enough U.S. support, could push Assad out of Damascus.

Gordon thought the opposition’s smaller, less-equipped force was no match for Syria’s Russia-backed military, and the eventual rise of the militant group Islamic State made defeating it a more pressing mission. Nothing short of U.S. entry into the war would change the battlefield’s dynamics, and no one around the Situation Room table—least of all President Barack Obama—wanted that.

“You do have to think about the next step before demonstrating your power to show you’re just as tough as the next guy," Gordon told Charlie Rose during an interview in October 2015, six months after leaving the White House.

Gordon’s overall observation—that there are limits to American power—came about after years of seeing American interventions fall short.

In a book he wrote about America’s regime-change failures in the Middle East, he laid out the examples backing up this view: A full-scale intervention in Iraq deposed Saddam Hussein but failed to establish a democratic beachhead in the region. Supporting allied airstrikes on Libya led to the death of Moammar Gadhafi but further destabilized the country. And the limited Syria intervention only created more problems that extended into Europe and the U.S.

“What I’m suggesting is the need to bring a certain humility to the notion that there is some simple solution to any of these big challenges," he told The Atlantic’s Jeffrey Goldberg in 2016. “It would be very surprising if, in fact, there were ‘right’ answers to Iraq, Libya, and Syria, and two successive administrations just applied the wrong ones to the wrong issues."

This view has led some to brand Gordon a restrainer, resistant to the full use of American power abroad. Top Republicans brand him as weak, even dangerous, on the global stage, citing his support for the Iran nuclear deal and his open criticism of the Trump administration’s “maximum pressure" campaign on Tehran.

But Gordon defies easy categorization.

In 1999, while serving on President Bill Clinton’s National Security Council, Gordon supported military strikes on Serbian forces to get them out of Kosovo. Even then, he would note, it took nearly 80 days and the full brunt of NATO might to achieve that limited objective. Then in 2013, Gordon advocated for bombing Syria after Assad killed 1,400 people with chemical weapons. He wanted Obama to enforce his “red line," though the president backed away from his threat.

Gordon is also a full-throated supporter of the U.S. effort to defend Ukraine, aiming to uphold the concept of sovereignty by punishing Russia for invading its neighbor. But Gordon, who also served in the Obama administration as the State Department’s top Europe official, has long been a Russia hawk.

In 2018, four years before the Kremlin’s all-out incursion into Ukraine, Gordon co-wrote an article in Foreign Affairs effectively proposing a set of policies—sanctions, persuading social media to combat disinformation, leaking embarrassing information about Vladimir Putin, among other moves—to perpetually counter Moscow.

“If this package of measures sounds like a prescription for a new Cold War with Russia, it is," he wrote.

And while Gordon is an evangelist for diplomacy, he is often cautious about a negotiation’s chances of success. As Kerry traversed the Middle East seeking a peace agreement for Israelis and Palestinians, Gordon often briefed the secretary and other Obama administration officials that neither side wanted a deal.

In particular, Gordon thought that Israeli Prime Minister Benjamin Netanyahu was unmovable, seeing no benefit to his political position in making nice with the Palestinian Authority.

“He lived the experience of Bibi moving the goal posts, making commitments and then pulling them back," said Ben Rhodes, a top national security aide to Obama, using the Israeli leader’s nickname. “It’s kind of the exact same thing that Bibi’s been doing in these cease-fire negotiations."

Officials say Gordon has proved effective at interfacing with allies and adversaries and leaning on relationships he has built over a long career and his ability to speak several languages. A French diplomat proudly labeled Gordon—author of a dissertation on French defense policy and translator of a book by former President Nicholas Sarkozy—a Francophile.

“European experience was very helpful on the Middle East, particularly on Iran," said Susan Rice, who was national security adviser from 2013 to 2017, noting the role of trans-Atlantic allies in securing a nuclear deal with Tehran.

Gordon makes his points quietly, professorially, with a slight British accent that comes from having lived in England. (His wife is originally from Great Britain.) He is known for avoiding direct interventions in meetings, preferring to keep his views private until they need to be shared.

The question now is, How will Gordon’s experience translate to advising Harris today, and potentially from 2025 onward?

Even though Gordon joined Harris’s first presidential campaign, they never established a personal rapport. But Gordon has been with Harris since Inauguration Day, and as he moved from deputy to the top job, their professional relationship grew further. Gordon has prepared Harris for meetings with more than 150 world leaders, countless global conferences and intelligence briefings with the president.

“The vice president really trusts him," said a former senior U.S. official. “He’s the last person in the room with her before she’s the last person in the room with the president."

Write to Alexander Ward at alex.ward@wsj.com