IT IS no secret that the Islamic State brought many tragedies. Potentially the most consequential of these is that in Iraq the rule of the erstwhile caliphate encompassed perhaps the world’s single richest trove of cultural heritage.

Now, as ISIS territory disappears yard by yard from the Iraqi map, it is time for the United States to start planning a “cultural surge” for this extraordinary pocket of the Middle East. Genesis locates the Garden of Eden closer to Basra, five hundred miles south. But it is Mosul and the neighboring Nineveh Plain that are the closest things on Earth to an Eden of civilization.

Home mostly to numerous ancient sects of Nestorian, Catholic and Orthodox Christians, but also to Shabaks, Yazidis, Kurds and Mandaeans—and more recently to Sunni and Shia Arabs—Nineveh has, for most of history, been populated by descendants of the ancient Assyrians. Jews were there from Babylonian times until the 1950s. Various Iranian invasions brought Persians. The Ottomans brought today’s Turcomans. There are Armenians and Circassians. The many languages of the Nineveh Plain include the tongues of Mohamed, Zoroaster and Jesus.

Nineveh’s cultural wealth reflects the appeal, to the tides of invaders over the millennia, of its rich agricultural plain. These are almost the only lands in Iraq that yield perennially rich harvests without irrigation.

Today the wheat on the Nineveh Plain is waist high again. Dotted with tidy rectangular plantations of tomato or watermelon, it rolls in golden waves to every horizon. The blackened villages are mostly ghost towns. Inside the churches, the debris has mostly been swept into piles. A few families return by day to sift through the rubble, begin repairs to their houses, or sell Pepsi and cucumbers to their scarce neighbors.

In west Mosul, the ravaged shell of the Mosul Museum is, depending on the day, a few yards or a few streets on one side or the other of the frontline. (Since my recent visit it has changed hands at least twice.) Amidst the rattle and booms of the fighting, Layla Salih stands inside the charred carcass of her office. An employee of Iraq’s State Board of Antiquities and Heritage, Salih is head of archaeology and heritage buildings for the Nineveh Governorate. The walls and ceiling around her are blackened. Rubble is shin-deep all around.

“We have no budget to fix any of this,” Salih tells me. Amidst the wreckage, there is no sign of her desk. There are no files, bookshelves, or chair. “We can barely protect the archaeological sites. How can we rebuild our country if we cannot save our past? In Iraq, the ancient heritage is the one thing that brings us together.”

As we pick our way out of the building, we pass the throne of Ashurnasirpal II, a noted sadist of the ninth century BC who “washed his weapons” in the Mediterranean and boasted of torturing his captives. “From some I cut off their noses, their ears and their fingers,” the Assyrian empire-builder says in an inscription. “Of many I put out the eyes . . . The young men and maidens I burned in the fire.” Pointing out his massive royal seat, now a knee-high pile of broken gray alabaster, Salih mentions that her salary has not been paid for the last two months.

Also inside Mosul city, but east of the Tigris and liberated in January, is Nabi Yunus—the tomb of Jonah. Here, ISIS destroyed the ancient shrine and dug half a mile of tunnels to loot the Assyrian palace beneath. In the low, narrow, crooked tunnels, it is impossible to tell whether the occasional, deep unnerving thunder is an allied air strike or an ISIS car bomb. A discarded orange jumpsuit, eerily lit by a cellphone, attests the slave labor that performed much of the caliphate’s rough archaeology. According to Salih, of the twenty-odd heritage sites in Nineveh Province administered by the Ministry of Culture in Baghdad, all have been damaged by ISIS, many severely.

The most important of these, and the most destroyed, is Nimrud, twenty miles southeast in the plain. This was Ashurnasirpal’s principal palace, built with war captive slave labor of his own. Picking her way carefully over the broken walls from Ashurnasirpal’s palace, wary of booby-traps and unexploded ordinance, Salih estimates that with bulldozers and explosives ISIS has destroyed about 90 percent of the ancient palace. The ancient perimeter walls once measured five miles around. The site, to the naked eye, is far too large for the handful of bedraggled guards assigned to protect it. Salih says that guards are paid by UNESCO.

“We need security. We need salaries . . . ” she says. “We must retrieve what has been looted. We can fix much that has been smashed. The losses need to be catalogued. We have to document the condition of dozens of sites.”

Where will the money come from for all of this? “Our old budgets were barely enough,” Salih says. “Now Daesh has taken us back to Year Zero in almost everything. Our needs are greater than ever but the politicians in Baghdad seem to be punishing Mosul and Nineveh.”

The Antiquities Board, with four hundred priority locations in Nineveh Province alone, has a budget. But little if any of it, says Salih, comes to the northwest of the country, where the city is dominated by Sunnis and the countryside by Christians and other religious minorities. The Iran-dominated Shia faction of former Iraqi prime minister Nouri al Maliki controls the antiquities board.

IN TERMS of antiquities, the priorities in Nineveh are to stabilize and document the status of the province’s four principal sites: Nimrud, Nebbi Yunus, Kuyuncik (site of the Biblical city of Nineveh) and Khorsabad (home to Sargon II, who collected tribute from Palestine to Persia). Then will come the more expensive work of restoring these locations and continuing the archaeology.

More recent parts of the heritage, such as the Mar Elia Monastery (closed since the Persians slaughtered the monks in 1743, partly vandalized by Americans in 2003 and destroyed by the Islamic State in 2014) need the same treatment. These plus the Mosul Museum would constitute a priority “action list” of five to ten physical locations.

In terms of living heritage, “There are about fifteen villages and small towns that provide the core of the human ecosystem of the Nineveh Plain,” says Maan Ajaj, director of the provincial council’s Nineveh Reconstruction Project. “These must be brought back to life in a lasting, sustainable way,” he says. At the smaller end in size is Batnaya, with about a thousand Aramaic-speaking Chaldean Catholic families before the Islamic State. At the larger end is Qaraqosh, a Syriac Catholic and Syriac Orthodox town with a pre-ISIS population of sixty thousand.

In each of these, churches and temples need to be restored and services, such as electricity and water, must be brought back. (Thanks to the absence of water and electricity, the provincial government currently does not allow people to stay overnight.) The former residents, eager to return, will do much of the work, Ajaj says. “But first they need to feel safe,” he says. “You will see: this is the only place in Iraq where you can truly say, ‘If this place is healthy, Iraq will be healthy.’”

Security and reconstruction in about twenty-five towns, villages and cultural sites: it is a tall order. But this region has likely seen more invasion and bloodshed over the millennia than anywhere else in the world. It owes its splendid diversity to those waves of invasions and it is good at bouncing back. “We don’t want the Christians of the Nineveh Plain to end up like its Jews,” says Ajaj. The children of the Captivity never returned to Nineveh after being driven out following the first Arab-Israeli War in 1948.

AS WELL as the wheel, government and religion, Iraq has given the world the new meaning of the word “surge”—a planned, coordinated and public dedication of new resources directed towards an urgent task. The last such U.S. project in northwest Iraq, in 2007 and 2008, was based on recognizing the primacy of local sentiment in any counterinsurgency. That surge was immensely successful. Today, as the caliphate dies in Iraq, it is time to start planning a new one for Mosul and its environs.

The new surge—focused on reconstruction rather than counterinsurgency—should be cultural. The project will do much to ensure Americans need not return here to fight again. It would serve two main purposes.

First: for Iraq, even more than everywhere else, cultural heritage is a powerful palliative, harmonizing force. Nothing else in Iraqi public life—apart, occasionally, from the national soccer team—comes close in this way. Antiquities heritage is national. It is nonsectarian. It is morale-lifting, proud-making and, above all, unifying. Cultural heritage that predates sectarian and political divisions ideally serves as bedrock. In Iraq, this heritage is greater and more important than perhaps anywhere else in the world. So are the divisions that it can heal.

Second, Nineveh is Iraq’s bellweather region and the national “cockpit,” in the old sense of that word. As things go here, so goes Iraq. Iraq will only ever be as good as its response to its own diversity, and Nineveh Province, including Mosul, is far more than anywhere else where the nation’s ailment lies, and its cure. That is why this is where ISIS was at its worst.