Her earliest works are all self-portraits: the young woman with her round face and unruly hair and brows so heavy they seem to be pressing her eyelids shut. So, too, are her very last, the face of an old woman worn out by living and mourning, as unsentimental as a Rembrandt. Yet there are still those eyes, peering out of their dark sockets, refusing to turn away.

Artists orient us. Where they look, we look too. Käthe Kollwitz never turned away from the world, or from herself—a real accomplishment in an age of mass movements and mechanically reproduced agitprop. Her orientation toward suffering both included and surpassed her own, as the Museum of Modern Art’s exhibition Käthe Kollwitz reminds us.

Born Käthe Schmidt into a family of East Prussian socialists, the artist was raised in a household where both politics and morality had a radical charge. Her maternal grandfather supported the revolutions of 1848, and founded the first Free Evangelical Congregation in Königsberg. Her father, a stonecutter, had trained as a lawyer but felt he could not ethically practice under the authoritarian Bismarck. He encouraged her to pursue art, and after her 1884 engagement to the medical student Karl Kollwitz, she studied painting at the Berlin and Munich schools for women artists (women were still not permitted to enroll at the state-run art academies).

In 1891, Käthe and Karl moved to a working-class neighborhood in northeast Berlin, where he opened a medical practice and Kollwitz made her studio. The couple had two sons, Hans and Peter, both of whom survived infancy. This was something of a miracle at the time: at the turn of the century, about one out of every three German children did not live past the age of five, and three of Kollwitz’s six siblings had died as children. From first to last, she returned to images of grieving mothers and lost children, beginning with the poor women who came to Karl’s clinic.

Kollwitz was equally adept at etching, lithography, sculpture, pastels, and charcoal; later in life she became a master woodcutter, producing the stark, agonized images that have become her best known. MoMA’s retrospective brings much of this together, placing her multifaceted works side-by-side, and explaining the context for her many pursuits. Printmaking has a long history among German artists, stretching back to Holbein and Dürer, and early works like “The Downtrodden” (1900) call back to the classic tradition, deploying both classical and Christian imagery in a darkly detailed chiaroscuro style. The technique was also popular among Kollwitz’s modernist contemporaries like Munch, for whom the easy repetition of images opened up new avenues of experimentation with color and superimposition.

Yet for Kollwitz, printmaking also had a strong political dimension. She chose reproducible mediums so that her images of working-class Berlin might reach the widest possible audience. Her carefully refined illustrations appeared in illustrated magazines and on political posters. But even Kollwitz’s most expressly polemical art is attentive to human frailty, and to all those small details—what John Berger called her earrings of hope—that make a figure something greater than a symbol, and imbue the political prisoner or the starving mother with vividness and life.

Kollwitz belonged to a generation of German socialists who believed in the potential of revolutionizing the nation from within. She showed her work at the very first Berlin Secession and campaigned to get women accepted into the Prussian Academy for the Arts. Even her most despairing images of poverty have something of that prototypical dignity that one often finds in the best political art, solemn figures holding up under the burden of their suffering. Her Peasants’ War series portrays violent revolution as both awful and necessary, a series of dynamic prints in which groups of men rush onward like a river. Yet these events are far enough in the past to stir without destabilizing.

Along with many of her left-wing contemporaries, Kollwitz initially supported Germany’s entrance into World War I. She even gave her eighteen-year-old son Peter permission to enlist, though he was too young to volunteer. He was killed in October 1914, ten days after his deployment to Belgium. His death shattered her, and she never recovered. The first woodcut from her War series of the early 1920s shows a naked, eyeless woman offering her child up to the sky. She titled it “The Sacrifice.”

It shows a public gesture, an expression of guilt and grief rendered in jagged black and white. Yet it also mirrors another, far more private image from before the war. In 1908, Hans contracted diphtheria and nearly died. In a series of charcoal illustrations, Kollwitz shows herself holding on tightly to her infant son’s face, struggling to hold back the skeletal arm of death that has gripped him around the waist. The image is poised between defiance and sorrow, the experience of a woman still so close to devastation that she is not able to let go. Now, she and millions of other German mothers were isolated in their collective mourning, unable to protest or publicly question the cause for which their children had died. “Is there anything at all that justifies this?” she asked, and became a pacifist.

For the rest of her life, Kollwitz followed this path from personal grief to universal sorrow. Her work became stark, full of mothers scrambling desperately to protect their children. The act is full of love, but hopeless: the children peer out from under protective arms, eager to race off to death. War “begins with glory,” she wrote, “and ends all in black.” Employing the harsh qualities of the woodcut, she eschews setting and character and even individuality, transforming her grieving parents and wounded widows into bare geometry, black figures on cream backgrounds, their individuality annihilated by grief. Contemporaries like Otto Dix used the woodcut to illustrate the stomach-turning grotesquery of trench warfare; Kollwitz’s austere prints strike at the heart. “Sorrow,” she wrote, “is all darkness.” No light, no earring of hope, no escape.

In their willingness to unsettle and upset, these images bring to mind Goya’s Desastres de la Guerra. As Sontag noted, those works represent “a synthesis. They claim: things like this happened.” But where Goya often focuses on perpetrators, even in her more militant early work Kollwitz attended only to victims. The aggressors are off-stage, abstract, known to all but unseen. At the end of her life, when she had been forced out of the Academy and forbidden by the Nazis from showing her art publicly, Kollwitz expressed her sorrow through archetypal symbols: children, mothers, the hand of death.

The mother’s embrace becomes the ultimate gesture. In his Pietà, Michelangelo focuses on the son, whose body is spread out as if on display, supported by the mother. But in Kollwitz’s work, the focus is on the mother who clings to her son, unwilling to let go. Kollwitz always orients us toward the mother’s sorrow, rather than the son’s suffering. Perhaps Michelangelo could imagine being laid out like Christ, but Kollwitz knew what it was to be Mary.

This highly emotional quality gives what survives of Kollwitz’s late work its overwhelming power. “The Lamentation,” a silver-painted plaster cast from the early 1940s, presents the artist’s face as a product of geology, eroded by grief into a kind of archetype. Her sorrow becomes unbounded, no longer the product of her time but eternal, a grief that will survive our own. Perhaps this is inevitable: despite all their Napoleonic garb, Goya’s Desastres have also assumed a strange timelessness; they speak now as a condemnation of war itself, any war at any time.

On October 17, a five-year-old girl named Saly was killed by an Israeli airstrike in Khan Younis. In the award-winning photograph taken by Reuters photographer Mohammed Salem, the child’s small body is cradled in the lap of her aunt, Inas Abu Maamar. Inas has her hand to the girl’s shrouded face. The aunt has hidden hers in the crook of her left arm, conveying the whole of her sorrow in the way she holds her niece’s body, as if to comfort or protect her. As of May 8, more than 14,500 Palestinian children have been killed in the Israeli war in Gaza. Perhaps in a hundred years Salem’s photograph will become like Robert Capa’s, a testament to horror and sorrow. Yet as I write, it is a document of an ongoing humanitarian catastrophe. How many other Pietàs have been enacted in private, without a photographer to capture them? How many more will there be before a ceasefire?

There are some who believe that politics always corrupts art. But as Kollwitz’s work reminds us, an artist lives in and responds to her world. Her vision, her orientation, determines everything. It is not a question of looking away. If you don’t want to see any more Pietàs, then help end the killings.