The American press largely supported Judge Irving Kaufman’s decision at the height of the Red Scare to sentence Julius and Ethel Rosenberg to death. In March 1951, a jury found the couple guilty of sharing state secrets about the atomic bomb with the Soviet Union. But it was up to Kaufman to determine an appropriate penalty — which, he decided, would be death by electrocution.

In April 1951, columnist Dorothy Thompson protested the judge’s sentence. Singular among American journalists for many reasons, including her gender, Thompson insisted readers appreciate the context in which the Rosenbergs had passed information to the Soviets. She asked why sharing “secret information” with a “foreign power in 1944, in wartime” was treasonous when that power was “not an enemy but an ally.” Thompson reminded readers that, in 1944, the U.S. and U.S.S.R. were working together to defeat Nazi Germany. Admiring the Soviets at that time, Thompson wrote, would not have been unusual for “the most respectable citizens,” let alone for two Jewish American Communists living on New York’s Lower East Side. “Indeed, it is unlikely that had they been tried in 1944,” Thompson wrote, “they would have received any such sentence.”

It is to writer Anne Sebba’s credit that by the time readers of her new book on Ethel Rosenberg arrive at Thompson’s objections, they appreciate both the full injustice of Judge Kaufman’s sentence and the clarity of Thompson’s analysis. In Ethel Rosenberg: An American Tragedy, published in June, Sebba presents little new information about the couple, whose activities during World War II, trial, and execution have been mined in works of fiction and nonfiction for more than 70 years. What Sebba offers is a fresh, psychologically minded cultural biography of Ethel herself. Sebba positions her subject as a victim of American post-war political and gender beliefs, a pawn in unethical prosecutors’ attempts to force Julius to confess and name names, and — most grippingly — a sibling caught up in vicious family dynamics beyond her control.

Sebba, who is English, has made a career of focusing on the history of women — some famous, others less so. In 2007, she profiled Winston Churchill’s mother in American Jennie: The Remarkable Life of Lady Randolph Churchill. In That Woman, published in 2014, she wrote about Wallis Simpson, the American divorcée for whom King Edward VIII of England abdicated his throne. More recently, in 2016, Sebba tried her hand at group biography in Les Parisiennes, an account of the ways women in Paris survived Nazi occupation.

Sebba spent five years researching her subject. She pored over archives, read published works, and interviewed friends, therapists, and surviving family (including sons Michael and Robert Meeropol) to create a briskly paced, three-dimensional portrait of Ethel, whom she deems innocent of the criminal and moral charges levied against her.

Sebba tells Ethel’s story chronologically, beginning with her childhood in the Lower East Side tenements. She presents the trial against Ethel and Julius in excruciating detail, describing their imprisonment and limited interactions with their children. Sebba goes beyond Ethel’s execution to end with the many ways writers and filmmakers have projected their own often misguided understandings and beliefs onto Ethel. Sebba’s exploration of the case against Ethel is particularly strong, with detailed analysis of the strategies of both prosecution and defense. Throughout, Sebba characterizes Ethel as “obstinate, determined, prone to self-doubt,” someone who “did not make friends easily,” and “highly intelligent and fiercely loyal to her beloved husband.”

Sebba rejects the commonly held views of Ethel in 1951. When Ethel was executed, most Americans believed that she dominated her husband. They also believed that when, during her trial, Ethel repeatedly exercised her right to plead the Fifth Amendment, she adopted a legal strategy whose end effect was to abandon her two young sons to a life without parents.

Despite the book’s many strengths, it is weakened by several missteps. Sebba likens a “belief in Communism” to “a version of the American Dream.” Perhaps because she is English, Sebba fails to appreciate that the American Dream is based on a belief that any individual can access opportunity, especially regarding private property. The American Dream stands in opposition to Communism’s emphasis on the power of an organized collective to redistribute wealth equitably and reliably. Sebba might better have described Ethel’s vision as utopian.

Additionally, Sebba characterizes Thomas Paine’s Common Sense as a “left-wing classic,” a description that fails to anticipate the ways those on the Right have used the Revolutionary-era pamphlet to justify everything from an expansion of gun rights to states’ rights.

While not a misstep, Sebba’s decision to include her own conjecture can at times be irritating. She explores Ethel’s thoughts and feelings as a parent, especially in relation to Michael, her older son. Michael was a high-strung, difficult child. Sebba writes that Michael’s behavior was challenging “possibly because he instinctively picked up on Ethel’s nervousness about trying to do her best.” Aren’t some children just wired to be anxious and difficult? Sebba supposes that Ethel ceased to participate in left-wing activism because she was “concentrating on motherhood, probably through a fear of abandoning her children.” Don’t some mothers of young children take a break from public life when they are exhausted?

I found it odd, given her inclination towards psychological analysis, that Sebba did not consider the concept of transference when describing love letters Ethel sent to a therapist who visited her while she was imprisoned at Sing Sing. Why not frame this one-sided love in terms of a doctor-patient relationship, not simply as a declaration of sad and desperate romantic longing?

As I came to the end of Sebba’s book, I felt conflicted. I was still savoring Dorothy Thompson’s assessment of Ethel Rosenberg’s trial and wondering if anyone could outdo her pithy summation.  But even with its flaws, and even though we know so much now about Julius and Ethel’s activities in the 1940s, Sebba enlightens. She has written a work in which Ethel is the main character, rather than an ancillary one. I understand Ethel and Cold War America better for having read it.