. . .

Befriending Keane wasn’t just about cultivating a single adviser. It gave Clinton instant entree to his informal network of active-duty and retired generals. The most interesting by far was David Petraeus, a cerebral commander who shared Clinton’s jet-fueled ambition and whose life stories would mix heady success with humbling setbacks. Both would be accused of mishandling classified information — Clinton because of her use of a private server and email address to conduct sensitive government business, a decision that erupted into a political scandal; Petraeus because he had given a diary containing classified information to his biographer and mistress (he was eventually charged with a misdemeanor for mishandling classified information).

On Clinton’s first trip to Iraq in November 2003, Petraeus, then a two-star general commanding the 101st Airborne Division, flew from his field headquarters in Mosul to the relative safety of Kirkuk to brief her congressional delegation. “She was full of questions,” he recalls. “It was the kind of gesture that means a lot to a battlefield commander.” On subsequent trips, as he rose in rank, Petraeus walked her through his plans to train and equip Iraqi Army troops, a forerunner of the counterinsurgency strategy in Afghanistan. It worked to their mutual benefit: Petraeus was building ties to a prominent Democratic voice in the Senate; Clinton was burnishing her image as a friend of the troops. “She did it the old-fashioned way,” he says. “She did it by pursuing relationships.” When Petraeus was sent back to Iraq as the top commander in early 2007, he gave every member of the Senate Armed Services Committee a copy of the U.S. Army/Marine Corps Counterinsurgency Field Manual, which he edited during a tour at Fort Leavenworth. Clinton read hers from cover to cover.

Although Clinton’s reservations about the surge were valid — the stability that the additional troops brought to Iraq didn’t last — her opposition to it, like her vote for the war, came back to haunt her. This time, it was her ally Bob Gates who summoned the ghost. In his memoirs, Gates wrote that she confessed to him and the president that her position had been politically motivated, because she was then facing Obama in the Iowa caucuses. (Obama, he wrote, “vaguely” conceded that he, too, had opposed it for political reasons.) Clinton pushed back, telling Diane Sawyer of ABC News that Gates “perhaps either missed the context or the meaning, because I did oppose the surge.” Her opposition, she told Sawyer, was driven by the fact that at that time, people were not going to accept any escalation of the war. “This is not politics in electoral, political terms,” Clinton said. “This is politics in the sense of the American public has to support commitments like this.”

‘They knew that if they walked into the Situation Room and they had her, it made a huge difference.’

The next time she found herself in a debate over sending troops into harm’s way, she voiced no such reservations.

“We need maps,” Hillary Clinton told her aides.

It was early October 2009, and she had just returned from a meeting in the Situation Room. Obama’s war cabinet was debating how many additional troops to send to Afghanistan, where the United States, preoccupied by Iraq, had allowed the Taliban to regroup. The Pentagon, she reported, had used impressive, color-coded maps to show its plans to deploy troops around the country. The attention to detail made Gates and his commanders look crisp and well prepared; the State Department, which was pushing a “civilian surge” to accompany the troops, looked wan by comparison. At the next meeting, on Oct. 14, the team from State unfurled its own maps to show the deployment of an army of aid workers, diplomats, legal experts and crop specialists who were supposed to follow the soldiers into Afghanistan.

Clinton’s fixation with maps was typical of her mind-set in the first great war-and-peace debate of the Obama presidency. She wanted to be taken seriously, even if her department was less central than the Pentagon. One way to do that was by promoting the civilian surge, the pet project of her friend and special envoy to the region, Richard Holbrooke. “She was determined that her briefing books would be just as thick and just as meticulous as those of the Pentagon,” a senior adviser recalls. She also didn’t hesitate to get into the Pentagon’s business, asking detailed questions about the training of Afghan troops and wading into the weeds of military planning.

She resolved not to miss out on anything — a determination that may have been rooted in a deeper insecurity about her role in what was to become the most White House-centric administration of the modern era. On the morning of June 8, 2009, she emailed two aides to say: “I heard on the radio that there is a Cabinet mtg this am. Is there? Can I go? If not, who are we sending?” On Feb. 10, 2010, she dialed the White House from her home, but couldn’t get past the switchboard operator, who didn’t believe she was really Hillary Clinton. Asked to provide her office number to prove her identity, she said she didn’t know it. Finally, Clinton hung up in frustration and placed the call again through the State Department Operations Center — “like a proper and properly dependent secretary of state,” as she later wrote to one aide in a mock-chastened tone. “No independent dialing allowed.”

The Afghan troop debate, a three-month drama of dueling egos, leaked documents and endless deliberations, is typically framed as a test of wills between the Pentagon’s wily military commanders and an inexperienced young president, with Joe Biden playing the role of devil’s advocate for Obama. While that portrait is accurate, it neglects the role of Clinton. By siding with Gates and the generals, she gave political ballast to their proposals and provided a bullish counterpoint to Biden’s skepticism. Her role should not be overstated: She did not turn the debate, nor did she bring to it any distinctive point of view. But her unstinting support of General McChrystal’s maximalist recommendation made it harder for Obama to choose a lesser option. (McChrystal was later fired by Obama after his aides made derogatory remarks about almost every member of his war cabinet to Rolling Stone magazine; she was the exception. “Hillary had Stan’s back,” one of his aides told the reporter, Michael Hastings.)

“Hillary was adamant in her support for what Stan asked for,” Gates says. “She made clear that she was ready to support his request for the full 40,000 troops. She then made clear that she was only willing to go with the 30,000 number because I proposed it. She was, in a way, tougher on the numbers in the surge than I was.” Gates believed that if he could align Clinton; the chairman of the Joint Chiefs of Staff, Mike Mullen; the commander of Central Command, David Petraeus; and himself behind a common position, it would be hard for Obama to say no. “How could you ignore these Four Horsemen of national security?” says Geoff Morrell, who served as the Pentagon press secretary at the time.

Just as Clinton benefited from her alliance with the military commanders, she gave them political cover. “Here’s the dirty little secret,” says Tom Nides, her former deputy secretary of state for management and resources. “They all knew they wanted her on their side. They knew that if they walked into the Situation Room and they had her, it made a huge difference in the dynamics. When she opened her mouth, she could change the momentum in the room.”
Photo
Clinton visiting the demilitarized zone separating North and South Korea in 2010 as secretary of state. Credit Mark Wilson-Pool/Associated Press

David Axelrod recalls one meeting where Clinton “kicked the thing off and pretty much articulated their opinion; I’m sure that’s one that they remember. There’s no doubt that she wanted to give them every troop that McChrystal was asking for.” Still, Clinton didn’t prevail on every argument. After agreeing to send the troops, Obama added a condition of his own: that the soldiers be deployed as quickly as possible and pulled out again, starting in the summer of 2011 — a deadline that proved more fateful in the long run than a difference of 10,000 troops. Clinton opposed setting a public deadline for withdrawal, arguing that it would tip America’s hand to the Taliban and encourage them to wait out the United States — which, in fact, was exactly what happened.

In the final days of the debate, Clinton also found herself at odds with her own ambassador in Kabul, Karl Eikenberry. He, too, held different views than she did on the wisdom of a surge, which he put into writing. On Nov. 6, 2009, in a long cable addressed to Clinton — and later leaked to The New York Times — he made a trenchant, convincing case for why the McChrystal proposal, which she endorsed two weeks earlier in a meeting with Obama, would saddle the United States with “vastly increased costs and an indefinite, large-scale military role in Afghanistan.”

Much of Eikenberry’s analysis proved prescient, particularly his warnings about the threadbare American partnership with the Afghan president, Hamid Karzai. It carried an extra sting because he was a retired three-star Army general who was the commander in Afghanistan from 2005 to 2007. Clinton, who had not asked for the cable, was furious, fearing it could upset a debate in which she and the Pentagon were about to prevail.

What the cable made clear was the degree to which the Afghanistan debate was dominated by military considerations. While Clinton did raise the need to deal with Afghanistan’s neighbor, Pakistan, her reflexive support of Gates, Petraeus and McChrystal meant she was not a powerful voice for diplomatic alternatives. “She contributed to the overmilitarizing of the analysis of the problem,” says Sarah Chayes, who was an adviser to McChrystal and later to the chairman of the Joint Chiefs of Staff, Mike Mullen.

In October 2015, the persistent violence in Afghanistan and the legacy of Karzai’s misrule forced Obama to reverse his plan to withdraw the last American soldiers by the end of his presi­dency. A few thousand troops will stay there indefinitely. And for all of Clinton’s talk about a civilian surge, it never really materialized.

For Clinton, the Afghanistan episode laid bare a vexed relationship between her and Eikenberry, one of the few generals with whom she didn’t hit it off. A soldier-scholar with graduate degrees from Harvard and Stanford, Eikenberry was brilliant but had a reputation among his colleagues for being imperious. Clinton had a similarly chilly relationship with Douglas Lute, another Army lieutenant general with a graduate degree from Harvard, who also fought with Holbrooke. “She likes the nail-eaters — McChrystal, Petraeus, Keane,” one of her aides observes. “Real military guys, not these retired three-stars who go into civilian jobs.”

“There’s no doubt that Hillary Clinton’s more muscular brand of American foreign policy is better matched to 2016 than it was to 2008,” said Jake Sullivan, her top policy adviser at the State Department, who plays the same role in her campaign.

‘She wanted to give them every troop that McChrystal was asking for.’

It was De­cem­ber 2015, 53 days before the Iowa caucuses, and Sullivan was sitting down with me in Clinton’s sprawling Brooklyn headquarters to explain how she was shaping her message for a campaign suddenly dominated by concerns about national security. Clinton’s strategy, he said, was twofold: Explain to voters that she had a clear plan for confronting the threat posed by Islamic terrorism, and expose her Republican opponents as utterly lacking in experience or credibility on national security.

There were good reasons for Clinton to let her inner hawk fly. After the attacks in Paris and San Bernardino, Calif., Americans’ concern about a major attack on the nation spiked. A CNN/ORC poll taken after Paris showed that a majority, 53 percent, favored sending ground troops to Iraq or Syria, a remarkable shift from the war-weary sentiment that prevailed during most of Obama’s presidency. The Republican candidates were reaching for apocalyptic metaphors to demonstrate their resolve. Ted Cruz threatened to carpet-bomb the Islamic State to test whether desert sand can glow; Donald Trump called for the United States to ban all Muslims from entering the country “until we are able to determine and understand this problem and the dangerous threat it poses.”

Yet such spikes in the public appetite for mili­tary action tend to be transitory. Three weeks later, the same poll showed an even split, at 49 percent, on whether to deploy troops. Neither Trump nor Cruz favors major new deployments of American soldiers to Iraq and Syria (nor, for that matter, does Clinton). If anything, both are more skeptical than Clinton about intervention and more circumspect than she about maintaining the nation’s post-World War II military commitments. Trump loudly proclaims his opposition to the Iraq War. He wants the United States to spend less to underwrite NATO and has talked about withdrawing the American security umbrella from Asia, even if that means Japan and South Korea would acquire nuclear weapons to defend themselves. Cruz, unlike Clinton, opposed aiding the Syrian rebels in 2014. He once supported Pentagon budget constraints advocated by his isolationist colleague, Senator Rand Paul of Kentucky. Thus might the gen­eral election present voters with an unfamiliar choice: a Democratic hawk versus a Republican reluctant warrior.

To thwart the progressive insurgency of Senator Bernie Sanders of Vermont, Clinton carefully calibrated her message during the Democratic primaries to align herself closely with Barack Obama and his racially diverse coalition. But as she pivots to the general election, that balancing act with Obama will become trickier. “There’s going to be a huge amount of interest in the press to score-keep,” Sullivan says. “It just so easily can become a sport that distracts from her ability to make an affirmative case.”

In showing her stripes as a prospective commander in chief, Clinton will no doubt draw heavily upon her State Department experience — filtering the lessons she learned in Libya, Syria and Iraq into the sinewy worldview she has held since childhood. Last fall, in a series of policy speeches, Clinton began limning distinctions with the president on national security. She said the United States should consider sending more special-operations troops to Iraq than Obama had committed, to help the Iraqis and Kurds fight the Islamic State. She came out in favor of a partial no-fly zone over Syria. And she described the threat posed by ISIS to Americans in starker terms than he did. As is often the case with Clinton and Obama, the differences were less about direction than degree. She wasn’t calling for ground troops in the Middle East, any more than he was. Clinton insisted her plan was not a break with his, merely an “intensification and acceleration” of it.

It’s an open question how well Clinton’s hawkish instincts match the country’s mood. Americans are weary of war and remain suspicious of foreign entanglements. And yet, after the retrenchment of the Obama years, there is polling evidence that they are equally dissatisfied with a portrait of their country as a spent force, managing its decline amid a world of rising powers like China, resurgent empires like Vladimir Putin’s Russia and lethal new forces like the Islamic State. If Obama’s minimalist approach was a necessary reaction to the maximalist style of his predecessor, then perhaps what Americans yearn for is something in between — the kind of steel-belted pragmatism that Clinton has spent a lifetime honing.

“The president has made some tough decisions,” says Leon Panetta, who served as Obama’s defense secretary after Bob Gates, and as director of the C.I.A. before David Petraeus. “But it’s been a mixed record, and the concern is, the president defining what America’s role in the world is in the 21st century hasn’t happened.

“Hopefully, he’ll do it,” he added, acknowledging the time Obama has left. “Certainly, she would.”

This article is adapted from “Alter Egos: Hillary Clinton, Barack Obama and the Twilight Struggle Over American Power,” published this month by Random House.

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A version of this article appears in print on April 24, 2016, on page MM28 of the Sunday Magazine with the headline: H Is for Hawk. Today's Paper|Subscribe