Last week, my friend Alice wrote me about her despair and dismay over President Trump’s family separation policy involving undocumented immigrants at the border. Her reaction stood out from other critiques of the policy, because she saw echoes of her own story, one that has traumatized her since she was a teenager separated from her family at the hands of the U.S. government.

Alice, you see, was one of the nearly 120,000 American citizens and residents of Japanese descent who were forced into incarceration camps during World War II. She was separated from her parents for months and then suffered the ordeal of being sent with them to an incarceration camp. Like the thousands of others who were stripped of their basic rights as a result of the internment of Japanese Americans, Alice and her family lost their property, their community, their privacy and their sense of security. These experiences shaped the lives of internees long after their eventual release from camps — a lesson especially important as the Trump administration pivots toward a policy of family internment.

In its own way, the internment of Japanese Americans was a kind of “zero tolerance” policy. After the Japanese bombed Pearl Harbor on Dec. 7, 1941, the U.S. government debated whether the people of Japanese descent living on the West Coast — two-thirds of whom were U.S. citizens — constituted a security threat. As a first step, government officials arrested and interrogated community leaders who they feared might commit sabotage or espionage on behalf of Japan.

Alice’s parents were caught up in this early witch hunt. Alice was 15 and living in Norwalk, Calif., when authorities arrested her parents because they taught at a Japanese language school. Alice and her 18-year-old sister were at school when her parents were arrested; they came home to find them gone. Alice still recalls the trauma of that day, marked by the sharp awareness that she didn’t even get to say goodbye to her mother and father before they were taken away.

The arrests, unwarranted as they were, were just the first step in what soon became a policy of total exclusion. In February 1942, President Franklin D. Roosevelt ordered the evacuation and relocation of all citizens and residents of Japanese descent from the West Coast. Justified on the spurious grounds of wartime necessity and fueled by the racist notion that all Japanese were untrustworthy, the internment represented a massive violation of both civil and human rights.

For Alice, the evacuation order meant that she and her three older sisters had to pack up the house, try to dispose of the family property and figure out what to do with their dog, all without the guidance of their parents. Thousands of Japanese Americans were moved to temporary centers hastily constructed at fairgrounds and racetracks, much like Walmarts have been converted into temporary shelters for young migrants today. Alice spent months living with her sisters in a horse stall at the Santa Anita racetrack. The famous racehorse Seabiscuit, Alice pointedly recalls, had two stall spaces at Santa Anita, while she and her sisters shared just one for nearly 10 months.

Alice was eventually reunited with her parents in Jerome, Ark., in what the government euphemistically called a “war relocation center.” In reality, it was a detention center. Like the nine other camps that housed Japanese Americans during the war, it was located in an isolated area surrounded by barbed wire under the watch of armed soldiers. In Jerome, the family shared a single room in a barrack and, like other internees, faced harsh environmental and physical conditions. While Japanese Americans sought to make the best of their conditions by starting schools and organizing clubs, the camps had poor sanitation and inadequate medical care. The suicide rate among those held in the camps jumped by as much as four times prewar levels, according to a study by Gwenn M. Jensen.

The stress of family separation and incarceration had long-lasting consequences for internees. Japanese Americans lost 75 percent of their property. Some, like Alice’s parents, were not able to recover financially. After the war, her parents were forced to take work as domestics because they could not get teaching jobs.

The experience affected Alice, too. When she left the camp to attend college, she was shy and timid, remaining apart from most of the other students. She suffered this trauma alone:

Like many internees, she felt stigmatized by her time in the camps. She didn’t talk to her own children about what she had experienced — it took years for Alice to be able to share any of this with her own family or to realize that she had, in fact, done nothing wrong. For a long time, she thought it was her fault that the government took away her parents and her home. Even today, at 91, Alice is only just realizing that she, too, was a minor child separated from her parents and that she is still dealing with the trauma of her experience.

Trump responded to intense public criticism by ending his official policy of family separation. But don’t be fooled — the inhumane treatment of children and families won’t be solved by this executive order. There is no plan to reunite children already separated from their parents. As long as the Trump administration treats migrants fleeing violence and persecution as “invaders" — as long as he pursues a policy of detaining indefinitely anyone trying to cross the border — families kept together will still face the trauma of internment, as Alice’s family and so many others did in the 1940s.

This historical injustice of fighting a war against fascism while committing such acts of totalitarianism at home has been difficult to confront. Indeed, it took four decades for a formal reckoning with these violations. President Ronald Reagan formally apologized to Japanese Americans who had been interned by the U.S. government during World War II when he signed the Civil Liberties Act of 1988.

For Alice, the crisis today and her fear of “how damaged these kids are going to be for the rest of their lives” have pushed her into action. She recognizes how vital it is that Americans understand we have been down this path before. We cannot forget the lessons of internment as our national leaders callously dehumanize migrants for, in Trump’s words, “infesting" America. We must do better. We owe it to Alice.

Renee Romano is the Robert S. Danforth Professor and chair of history at Oberlin College, and her most recent book is ”Historians on Hamilton: How a Blockbuster Musical is Restaging America’s Past.”