THE FLIGHT FROM KUWAIT CITY was overbooked, and the American soldiers standing near the gate were hoping for upgrades. They were comparing notes with an accountant returning from her first trip to the region, keeping an eye on a man in a dishdasha, who paced in front of the empty counter, waiting for a chance to resume his tirade against United. He claimed that on the flight from Manama a drunken American had tried to open the emergency exit; nothing the gate agents said during the layover assuaged him, and now they were gone. Sometimes, inexplicably, he would drag his backpack across the floor, muttering loudly, in Arabic and English, about the perfidy of Americans. When two security officials came to take him away, the soldiers assured the accountant that he would not be allowed to board the plane to Dulles.

I had not noticed any irregularities on the first leg of my journey, perhaps because I was writing notes about my cultural diplomacy mission to Bahrain — a series of encounters, lectures, and creative-writing workshops organized by the American embassy for the University of Iowa’s International Writing Program, which brought me face to face with artists, students, and writers from the divided Shia and Sunni communities. The Arab Spring had left scores dead on this small island, and the Shia’s continuing protests against the American-backed Sunni monarchy suggested that more violence was in the offing. This dark knowledge informed the impressions that I recorded in my notebook, the last of which concerned the ancient fortress in Manama, Qal’at al-Bahrain, a tel containing in its sands layers of history and myth, from the epic of Gilgamesh and annals of Alexander the Great to the oil rush of our time.

Walking by the seawall, toward a palm grove, I was struck by the number of blank spaces in the archaeological record (three-quarters of this UNESCO World Heritage site remains unexcavated) and by the mysterious fact that Bahrain once possessed the largest cemetery in Arabia. In the museum was a display of ceramic bowls in which skeletons of sea snakes were coiled one on top of another. Archaeologists surmise that the tradition of snake sacrifice was the gift of traders from India, one of a succession of civilizations to leave a mark — Assyrian, Babylonian, Greek, Arab, Persian, Portuguese, British — a history of exchange in which the United States has assumed the leading military role. The navy’s Fifth Fleet, based in Bahrain, is responsible for the Persian Gulf, the Red Sea, and parts of the Indian Ocean, protecting shipping in the Suez Canal and the passage of oil tankers through the Strait of Hormuz. Bahrain is but a proxy in the regional struggle for power. Iran, Saudi Arabia, and the United States are all vying for influence here.

Which is fitting. The economic boom in the Gulf began in 1932 with the discovery of oil in Bahrain — the prelude to the rise of petro-states, OPEC, and Western efforts to ensure a steady supply of petroleum and natural gas. Perhaps it will end here, too. Bahrain’s reserves will likely run dry before 2030; with discoveries of oil in Brazil and Kenya and Mozambique, as well as the transformation of North America into an energy power through the development of natural gas fields in the United States and the shale oil industry in Canada, the strategic importance of the region may diminish. But this is still a rough neighborhood — marked by the Arab Spring, the Israeli-Palestinian conflict, the standoff over Iran’s nuclear program — which will continue to consume a disproportionate amount of diplomatic, political, and military energy.

It was after midnight when we boarded the plane. The Special Forces officer beside me was grateful to have an aisle seat: he had injured his back in a Black Hawk helicopter crash, and expected to get up often during the flight to stretch. He looked like an aging beach bum, with a blond ponytail and tan — he planned to spend his time off windsurfing on the Potomac — and he couldn’t wait to return to Afghanistan; thirty years of service had not diminished his zeal for his work. Turn and burn, he said of his multiple deployments, a useful description of how the post-9/11 American military has operated, in perpetual war, with a budget greater than the combined military spending of the rest of the world. This is unsustainable in the ongoing economic crisis, and the officer knew that change was coming. But he thought that there would always be a place for warriors with his particular skill set, on which he did not care to elaborate. He wondered why the plane was so full. He had heard something about a conference in Kuwait City. The date was December 14, 2011. What would not emerge until late the next night was that while we were in the air the last American troops in Iraq were preparing to leave their base, under cover of darkness so as not to attract insurgent fire, and travel overland to the border with Kuwait, where CNN was waiting to record the end of the occupation. We were all heading home.

THE GREEN FLEET

It is a truism that generals fight the last war, sometimes to their detriment, relying on strategies and tactics unsuited to a different battlefield. With the departure of American forces from Iraq and their impending withdrawal from Afghanistan in 2014, military planners sketching out future campaigns must take into account successes and failures in the war on terror, mindful that the next theater of operations may require new ways of thinking about the mission. War is a constant in human history, and military leaders are judged by their ability to assess gathering threats, which now include climate change, and prepare accordingly. Melting glaciers and ice caps, rising seas and incidences of severe weather, drought and wildfire — these must be factored into calculations about everything from terrain to weather to the length of supply lines.

As the Arctic sea ice shrinks, for example, and it becomes easier to extract the reserves of oil, natural gas, and minerals thought to lie under the ocean floor, competition for these resources will increase the likelihood of friction between governments with claims on this region. What was once unimaginable may one day seem inevitable: U.S. forces preparing for war not only against a traditional foe like Russia, but longstanding allies like Canada, Denmark, and Norway.

How the Pentagon will respond to future threats can be gleaned from its Quadrennial Defense Review (QDR), the most recent edition of which appeared in 2010. Like the insurance industry, the military recognizes that it cannot afford the luxury of remaining skeptical about climate change, the effects of which, the QDR notes, “are already being observed in every region of the world, including the United States and its coastal waters.” The military is thus “developing policies and plans to manage the effects of climate change on its operating environment, missions, and facilities.” This includes performing environmental stewardship at installations in this country, in the service of meeting “resource efficiency and sustainability goals.”

It may be comforting to learn that the Pentagon is determined to adapt to climate change and to reduce its dependence on oil — a policy initiated during the Bush administration, by then–secretary of defense Donald Rumsfeld, who said that a more efficient fighting machine could be built if it did not have to rely on oil from the Middle East. The logistics and security costs of transporting fuel to a battlefield can raise the price per gallon to $600; hence, for economic and security reasons, the Pentagon is exploring various alternative energy sources, from solar panels in Afghanistan to biofuels in fighter jets and ships.

Enter the Great Green Fleet (after President Theodore Roosevelt’s Great White Fleet, which a century ago announced the arrival of a new maritime power), a carrier strike group to be deployed by 2016, with biofuels powering its non-nuclear vessels. In recent military exercises in the Pacific Ocean, FA-18 Super Hornets using a mixture of jet fuel, cooking grease, and algae took off from the deck of the USS Nimitz, while two destroyers and a guided-missile cruiser sailed nearby, powered by a mixture of bio- and conventional fuels.

“There was no difference with the fuel,” said Ray Mabus, secretary of the navy, insisting that the exercise offered proof that biofuels can work in an operational environment.

While some critics object to the high cost of biofuels, Mabus insists that these costs will decrease as demand rises. Within the decade, the air force and navy will replace half of their petroleum needs with biofuels, and Mabus draws on the navy’s history of innovation — from sail to coal to oil to nuclear power — to argue that “at the time of each energy transformation, there were doubters and naysayers who said trading a known source of energy for an unknown one was too risky and too costly. But the navy pursued innovation because it improved the capability of the fleet and made us better war fighters.”

Nor should we overlook the fact that the Pentagon, which is responsible for 90 percent of the fuel used by the federal government ($16 billion in 2008), is a giant engine for economic growth. (Think: the internet, GPS, flat-screen televisions.) If the secretary of the navy is correct, the Great Green Fleet will become an emblem of a more sustainable future.

But this is only part of the story, as the QDR makes clear:

A series of powerful cross-cutting trends, made more complex by the ongoing economic crisis, threatens to complicate international relations and make the exercise of U.S. statecraft more difficult. The rising demand for resources, rapid urbanization of littoral regions, the effects of climate change, the emergence of new strains of disease, and profound cultural and demographic tensions in several regions are just some of the trends whose complex interplay may spark or exacerbate future conflicts.

Strategists have long recognized the connection between environmental stress and war. According to Michael Klare, an authority on the subject, “While many academics and politicians cling to the ‘clash of civilizations’ paradigm to explain world affairs, those who have been watching developments closely recognize that ethnic and religious schisms are often caused or worsened by competition over scarce supplies of land, food, and water.” Such competition will deepen as the climate warms, causing floods in some areas and drought in others. Rich croplands will become deltas or deserts: fertile conditions for extremists avid to exploit hunger and misery for their own purposes. This will likely lead to more conflicts, more calls for military intervention, more humanitarian and disaster-relief missions. The Pentagon must also plan for hurricanes, tornados, wildfires, and the flooding of its installations and training grounds. No fleet or army on earth will be able to manage all the problems that the changing climate will bring.

THE UNTHINKABLE

Soon after 9/11, in a seminar on lessons of the tragedy, an intelligence professional lamented the inability to synthesize information when the attack was looming — to connect the dots. After the seminar, I told her that I live in a place, Iowa City, known for cultivating the art of drawing connections, which we call teaching creative writing. She said that such thinking might avert further tragedies — an idea that inspired my call to a man with long experience in the field of preparing for the worst. William Smullen, director of the National Security Studies Program at Syracuse University and former chief of staff to secretary of state Colin Powell, convenes a two-week seminar every spring for military and civilian leaders to assess security challenges, provide strategic insights, and plan for the future. I asked him what most worries him.

“The threats are everywhere,” he said. “What keeps me awake at night is the thought that someone will get their hands on a WMD — biological, chemical, radiological — and set it off.

“The Cold War was easy,” he continued. “Now our forces are worn out, and there’s so much uncertainty in the world that no one can predict what kinds of wars we’ll wage in the future. We’ve been guilty of a lack of imagination, of an inability to think outside the box about what might happen. We have to think the unthinkable, in view of the fact that in the last ten years we’ve gone from being able to fight two regional contingency wars to one. By 2017 we’ll have a much smaller military. And the next wars will be insurgencies.”

He paused to reflect. Thirty years in the military, including two tours of duty in Vietnam and service as spokesman at the Pentagon, had taught him to choose his words carefully.

“Will another 9/11 happen?” he asked. “There are people out there trying to bring another catastrophic event to our soil. For instance, they’d love to start forest fires in California, Arizona, Idaho — all over the West. You can create a big fire very, very fast. I don’t want to sound pessimistic, but we’re in a very complex period. The fact that nothing like 9/11 has happened since may lull us into believing there’s nothing to worry about.”

EVERYONE CAN DRONE

It is a short distance from the forward operating base in Jalalabad, in eastern Afghanistan, to its adjacent airfield. But the security situation is so dire that Apache helicopters must ferry soldiers, diplomats, and aid officials back and forth across the road, convoys of mine-resistant armored personnel carriers being too expensive to organize. Our longest war is ending not with a whimper but with suicide bombings, often detonated by Afghan troops operating alongside Americans.

One winter morning, a diplomat and I boarded a helicopter for the five-minute flight and then took a bus to the edge of the runway, where we waited in our body armor at a red light, as if at a crosswalk. The diplomat was anxious about making our flight to Kabul, and as she studied a plane parked in the holding area across the way, debating whether it was ours, a Predator drone taxied past us and took off toward the mountains dividing Afghanistan from Pakistan. The light turned green, we lumbered across the tarmac, and a contractor met us at the foot of the stairs to the plane in the holding area. We were not on his flight manifest, so we waited for another plane, which eventually took us to Kabul. At dinner that night in the embassy, I mentioned to another diplomat that I had seen a drone take off toward Pakistan. “No, you didn’t,” she said.

This underscores the moral dilemma of waging war with unmanned aerial vehicles. It’s no secret that during the Obama administration the number of drone strikes has dramatically increased in preparation for the withdrawal of American troops from Afghanistan; while some voices have been raised in protest it has become clear that the information revolution has outpaced our ethical response, which is traditionally articulated by philosophers, theologians, and writers. We lack a language adequate to the expansion of surveillance, development of cyberwarfare, and deployment of drones. (How, for example, to make sense of the phrase collateral damage, which has become a commonplace of foreign policy discourse?) In an article from the New York Times, “The Moral Hazard of Drones,” the scholars John Kaag and Sarah Kreps remind us that

the creation of technology is a value-laden enterprise. It creates the material conditions of culture and society and therefore its creation should be regarded as always already moral and political in nature. However, technology itself (the physical stuff of robotic warfare) is neither smart nor dumb, moral nor immoral. It can be used more or less precisely, but precision and efficiency are not inherently morally good. Imagine a very skilled dentist who painlessly removes the wrong tooth. Imagine a drone equipped with a precision guided munition that kills a completely innocent person, but spares the people who live in his or her neighborhood. The use of impressive technologies does not grant one impressive moral insight.

Their warning should apply to anyone adapting military technologies for other purposes, including preservation of the environment: the most benign use of drones will not change what lies in the hearts of humans. Now everyone can drone! So reads the banner on www.ConservationDrones.org, which offers to share its knowledge about building low-cost drones “to help conservation workers and researchers in developing countries do their jobs a lot more effectively and cost efficiently.” The skies are rapidly filling with drones, which will surely serve every imaginable purpose under the moon and stars, from patrolling borders to monitoring loss of habitat to tracking poachers to advertising to, well, you name it.

The sight of that drone was on my mind when I went to the Friday market at the NATO base in Kabul. At lunchtime, soldiers, diplomats, and aid officials barter with local merchants for carpets, lapis lazuli, and relics of the Soviet order (medals, hats), and there I found a small clay bomb for sale, which dated from the Crimean War — a useful reminder that in this graveyard of empires there are certain constants: borders are drawn in blood; no one likes an occupying army; the battle for resources never ends. A hundred years from now, in a bazaar in Kabul, a traveler may find a drone that fits inside his hand and conclude that nothing has changed.

THE COOPERATIVE SPIRIT

Secretary of Defense Leon Panetta was in Hanoi, working out a new security arrangement with the Vietnamese military, on the day that our delegation of American writers arrived for a cultural exchange. What surprised me was the tangle of emotions that I experienced — sadness, regret, and exhilaration — at the energy on display in the capital of our former enemy. I grew up watching the carnage of the Vietnam War on television, which touched me only on occasion: when my baseball coach’s nephew was killed; when a Fourth of July parade ended with a protest; when a faux award ceremony was held during my freshman year of high school for the star football player who won the pool for receiving the lowest number in the lottery for the draft.

“I’d like to thank my classmates for this honor,” he said in his acceptance speech, “and Richard Nixon for prolonging the war, and my right knee for making me 4F.”

The suspension of the draft the next year sealed over that moment in history for me, and now a seam opened in my memory, widening by the minute — in our creative writing workshops; in a tea house with an aging Vietnamese novelist; at an exhibit of poster art from the war, with captions like Nixon has to pay with blood for our blood and Uncle Ho is still marching with us.

Our cultural diplomacy mission was part of the Obama administration’s strategic pivot toward Asia in reaction to China’s rising power — a soft-power counterpoint, if you will, to the small expeditionary force of marines recently deployed to Australia. Competition over access to minerals and oil, disagreements at the United Nations and other forums over security and trade issues, confrontations at sea between China and Japan, the Philippines, Malaysia, Indonesia, Brunei, and Vietnam — all carry the seeds of war. Our efforts to win the hearts and minds of Vietnamese literati, matched by our Chinese counterparts, belonged to that elusive realm of influence, strategic and cultural, which artists map at their peril. The genial officiousness of the apparatchiks accompanying us from the Vietnamese Writers’ Union, who had arranged our program, brought to mind apparatchiks from the Chinese Writers’ Association who had taken me and other American writers around their country. But if it was easier for Vietnamese writers to relate to Chinese writers they did not let on: it was in their interest as much as ours to find common ground in the face of China’s rising power.

For the fate of the earth is in profound ways being written in China, between its demand for natural resources and respect for the environment. “I sense that Chinese leaders are unsure of how to proceed on these critical issues,” Michael Klare explains. “On one hand, they favor energy efficiency and the development of green innovations; on the other hand, they show no inclination to soften their drive to gain control over all those islands in the East and South China Seas. This in turn is provoking increased opposition from neighboring countries, including key U.S. allies like Japan and the Philippines — thereby increasing the risk of a naval clash as the U.S. becomes more entrenched in the area as part of Obama’s ‘pivot’ strategy.”

On our last night in Hanoi the Writers’ Union hosted a dinner for us at a local restaurant, presided over by a former tank commander and two of his fellow soldiers, who joked about how easy it had been to kill Americans — how sorry they felt for them. Yet for all their bluster about winning the war they betrayed some insecurity, questioning me at length about the International Writing Program’s supposed preference for hosting South Vietnamese writers. I explained again (the question had been raised in many settings) that in my program North Vietnamese writers far outnumbered writers from the South. My hosts did not believe me, the dinner ended on a strained note, and when the Americans headed for the Old Quarter to shop, I decided to go for a walk around the lake, where couples were dancing to music blaring from boomboxes.

“The written history of the world is largely a history of warfare,” John Keegan writes in A History of Warfare, “because the states within which we live came into existence largely through conquest, civil strife or struggles for independence. The great statesmen of written history, moreover, have generally been men of violence for, if not warriors themselves, though many were, they understood the use of violence and did not shrink to use it for their ends.” He goes on to suggest that even though “the frequency and intensity of warmaking” in the twentieth century touched the majority of families in Europe, America, Russia, and China, the fact remains that “in their everyday lives, people know little of violence or even of cruelty or harsh feeling. It is the spirit of cooperativeness, not confrontation, that makes the world go round.”

This insight struck me when A History of Warfare was published in 1993. I was reporting on the siege of Sarajevo, the longest in modern history, where neighbors had turned against their neighbors and everywhere I looked was evidence to contradict Keegan. There was no gas, water, and electricity in the city that had just hosted the Winter Olympics; the only way to communicate with the outside world was by satellite phone or fax; civilians, especially children, seemed to be always in the sights of snipers and artillerymen. Yet Bosnians carried on with their daily lives, and for all the carnage and destruction, I nevertheless witnessed more acts of cooperation than of aggression, which convinced me of the essential wisdom of Keegan’s proposition.

Twenty years later, I still think he was right, although I am also haunted by a story that a soldier told me last winter in Kabul, which points to the strangeness of war in a wired world — the strangeness, that is, at the heart of the human condition, which from time immemorial has led us into battle. One day the soldier was walking around the base, arguing with his girlfriend on his iPhone, when the Taliban launched an attack — mortars, rocket-propelled grenades, small arms fire. He took cover behind an armored vehicle, still arguing with her, and he was trying to gauge the origin of the attack when she told him to hang up — which he refused to do. A shell whistled overhead, another landed just beyond him. Finally she said, What’s the matter with you?

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