Photographs like these first started circulating after World War I, largely in an effort to enlist art in the creation of a new international morality — to recruit aesthetics against warfare. Throughout World War I, various European and colonial monuments administrators not only took protective measures (removing museum objects to storage, boarding up urban statuary, installing guards around archaeological sites, and so on) but also documented all of this with photography.

In the following decades, the League of Nations tried to produce an international agreement forbidding the destruction of art and architecture. But this never succeeded, and instead this sandbagging-and-photographing system became increasingly codified as a visual language.

The Spanish Civil War was a major turning point. Spanish architects began to use bricks (which were less flammable and more available than sand) to protect monuments, and they also started experimenting with a striking new kind of constructivist architecture. Spanish artists additionally organized themselves into a junta, or league, making posters to educate anti-republican fighters not to destroy art or religious objects. And all of this was witnessed by the many international journalists who had come to cover the conflict.

By the late 1930s, the League of Nations published a manual on how to do these protective works. The fascist government in Italy had all its monuments photographed and published in “before-and-after” shots in 1942. By the end of World War II, an international norm had been born. But still, there was no codified law on protecting monuments. Instead, the new international order advocated for material protection via a moral code. When an agreement (the Hague Convention for the Protection of Cultural Property in the Event of Armed Conflict) was signed in 1954, it made rules that are still dependent on adjudicating moral claims.

Still today, sandbag protection measures are integral to preparedness for war. All modern armed forces claim to have plans for cultural protection — which is why we find it shocking when they are not implemented, as was the case in 2001 when the United States did not protect the National Museum of Iraq.

There are also always bureaucratic and financial obstacles. I recently corresponded with a museum director in Ukraine who waited in vain for the outdoor sculptures to be protected by the Ministry of Culture and Information Policy, and instead did it with his own staff. It is precisely to make up for this gap between policy and resources that photographs of sandbags are taken and sent to the Western press.

But the more these images circulate, and the more they arouse in us a universal disgust or pacifist outrage, the more we look at any given conflict in a moralizing way, and we forget that there is not a fundamental opposition between art and war. Instead, one can also read in these images the symptoms of very specific military and political struggles.

If you look closely at these photographs, you will see they are not only images of protection; they perform a kind of protection just by circulating. To be sure, the sandbags provide a limited protection against damage. But frequently, they show some part of the protected artwork still left uncovered — the head of a statue, for example — so that it can be recognized as art. Sandbag piles are photographed in a way that appeals to aesthetics to convey urgency. And sandbags make for an especially poignant visual message because they evoke mobilization from below. After all, a sandbag is a relatively low-tech solution: it can be carried by one person, and it is distributed empty, then filled with sand or earth on-site. These are photographed as if they were monuments to civilian resilience. In fact, merely by circulating and being shared, the images are also part of a distinctly liberal internationalism that evolved in the twentieth century very much from above: an ideology arguing that art is above war, that there is no politics in art.

There were two failures that led to the militarization of the cultural front during World War II. The first, as you note, was a failure of international law. Second, there was also a technical shortsightedness: a failure to predict the scale of destruction. Everyone underestimated the ramping up of aerial bombing and the consequence it would have: turning every monument into a possible target. In fact, insofar as anyone prophesized aerial bombing in the 1920s, they predicted that extensive bombing of cities would be so atrocious that it would shorten the length of wars. This is the opposite of what happened. Yes, aerial bombing became the weapon of choice, but it also prolonged the war. The very choice of targets came to have “cultural” meaning.

The real militarization of monuments protection, then, fell to American hands. The US Air Force had a penchant for precision bombing, which required making extensive lists of targets: they hired American industrialists to study German territory and list which nodal points would have to be bombed to weaken the war machine.

Making lists of cultural sites was in some sense a continuation of this practice — you just needed to recruit another kind of civilian expert, an art historian, to make those lists. There were many European émigré art historians in the United States, and they were chosen to make lists of art institutions and buildings that should not be bombed. They used existing tourist guides, in fact, as a basis for these lists.

The switch from bombing factories to not bombing monuments is also explained by an American preference, this time of strategists: for long-term planning for the occupation of enemy territory. Here, too, it was relatively easy for cultural diplomats to argue that expertise about the “cultural monuments” of European nations should be included in plans for how to run occupied territories when the United States won the war. The argument was that occupying forces would have an easier time governing if they were seen to be respectful of local culture.

As such, the role of cultural objects was transformed. Once parts of daily life, they became tools to normalize the unprecedented scale of violence.

UNESCO’s main terrain is “culture,” and it has worked hard to make this agenda compatible with international development programs and funding. Early in the 1950s and 1960s, this meant retiring older forms of cultural imperialism. Many postwar social scientists worked to convince the organization that you could devote budgets of “technical aid” to supporting the arts, as a step toward a democratization of culture.

But this technical turn was totally compatible with a certain kind of mass tourism, which has had its own problematic dimensions. There has also been some real damage to the built environment under the guise of cultural benevolence. This applies to making monuments visitable by tourists.

Until the 1980s, most international monuments missions recommended emptying a new path through a cultural site to make way for tourists. Their model was the church in a Western city: a sacred space only occasionally occupied by worshippers. Yet most sacred spaces around the world are cities and monuments all at once; they are inhabited, guarded, and maintained as part of religious and commercial life.

In my book, I tell the history of the temple of Srirangam in southern India, where a conflict emerged among the conservationists who wanted to teach people how to “conserve” their own wall paintings. But like the sacred spaces of most organized religions, the temple included a class of people whose role was to maintain sacred objects. Still, once UNESCO managed to establish the tourist path it was lobbying for, the path became entirely separated from the rest of the temple, cleared of people and of anything resembling the present — so that Western visitors could feel that they were visiting a bygone civilization.

One of the most underdescribed aspects of the postwar rise in restitution claims is that such demands went hand in hand with the proliferation of museums as part of nation-building during the process of decolonization. Innumerable governments from the 1960s onward asked for UN and NGO support in creating new national museums. Still today, any claim to restitution is dependent upon the presence of a climate-controlled museum to which objects can be returned.

I think that for its authors, the French report was a brave act of engaged scholarship. But governments have to be subjected to more scrutiny: for the French state, this report is an act of governance. Predictably, European states are now competing to remake their national image by engaging in hand-wringing about former colonies. But these questions of restitution are, of course, just the tip of the iceberg.

In that sense, the focus on restitution today is both a triumph of the liberal international order and a demonstration of its absurdity. The idea that the space of a museum is a space “free” of ideology has been completely challenged, but not from the outside. It has been challenged by those who want to use the global movement of art objects to undo the very Western institutions who claim to have invented it. But isn’t “culture” also a word that designates more informal life? Must culture always be institutionalized?