Even before Trump took office for his second term, trans people have been increasingly under attack. In 2024, a record of over 600 state and federal bills were introduced targeting trans rights. Increased transphobia over years has reinforced violence against trans people. Then, Trump took office and launched an onslaught of legal and ideological attacks on trans lives. 

Socialists have a particular duty at this time to stand firm in support of trans rights, and to explain exactly why it is that trans people are being used as a scapegoat by Trump and the Republican Party. This article is a part of an ongoing series of material in which we will explore a socialist approach to gender liberation in more depth. Read the first article of the series here.

Debating biology in sports has been a favorite pastime among right-wing culture warriors for years. We are constantly inundated with reports on “men competing in women’s sports” and long discussions about individual athletes’ biology. For the average person, it can be difficult to parse what constitutes an “unfair” biological advantage, and how that fits into the current state of competitive sports. Pundits like Michael Knowles take advantage of this confusion to scare people into believing trans people are a threat, particularly in women’s sports. 

The main right-wing talking points boil down to this: transgender and intersex individuals have an unfair biological advantage over cis (identifies with gender assigned at birth) women, and this poses an extreme threat to the safety of cis women.

Does Testosterone Define A Binary In Sports?

Testosterone is often cited as the biological difference between men and women that creates the need for sex-segregated sports and for policing women’s sports in pursuit of fairness. But is it? Caster Semenya is a cis female athlete with an intersex condition that produces increased testosterone. Following her win in the 2009 800-meter women’s World Championships, she was subjected to extensive sex testing and was ultimately banned from competing in that event. Semenya’s case led to a regulation on certain track and field events requiring competing women to have a testosterone level under 10 nmol/L (the low end of the normal range for cis men). Roughly 2% of people have an intersex condition—100 times more common than identical twins.

But what is testosterone and what does it do? Testosterone is a hormone, one of many chemical messengers that tell your body what to do and when. Testosterone is the main androgen, responsible for the development of what are generally considered “male” sex characteristics. Cis men have higher concentrations of testosterone than cis women, although wide variation exists in both groups. During puberty, testosterone promotes muscle development and increases hemoglobin concentration (which raises the body’s blood oxygen carrying capacity). This suggests that, on average, people who experience testosterone-based puberty have higher strength and aerobic capacity than people who do not. Yet we cannot predict the athletic ability of a specific individual based on their hormones. Athletic ability is not a single dimension, and testosterone is not a magical chemical that induces all-around athletic domination. 

Binaries can be useful for categorization and organization, but some, like the male-female sex binary, ultimately fail to accurately describe the vast nature of human biology. Distribution of sex characteristics is better represented as a bimodal curve, a continuum with clusters around two poles, often crudely labeled “male” and “female”, but with an overlapping middle (see image).  Characteristics—like height, body mass distribution, or even metrics of athletic performance—vary widely within each (“male” or “female”) cluster. This means that the difference between two given cis women can be wider than the difference between a given cis woman and a cis man. Even chromosomes do not determine a straightforward sex binary. XX is the most common female sex chromosome pair, and XY the most common male, but cis male XX’s exist as well as cis female XY’s. There are myriad intersex variations like XXY, mixes of XX and XY, and uneven gene expression. Whether trying to define biological sex by chromosomes, anatomy, or hormones, two rigid categories simply do not suffice.

How Do We Decide What’s “Fair”?

Currently, most sports are segregated along the sex binary in the name of fairness, but given that the binary is incorrect, how do we decide what is actually “fair”? Biological differences contribute to comparative athletic ability, but hormones are not the only factor, or even the most important. Hormones impact height, weight, and joint mobility, but there is much variability and no guarantee. There are men with high levels of testosterone who are under-average height and weight.

You might think that trans women would be stronger and faster than the average cis woman if they experienced testosterone-based puberty. However, research into trans athletes tells a different story. Several studies show that hormone treatment therapy (HRT) can erase this “advantage”. After 2 years of HRT, trans women show no statistical difference from cis women in their 1.5-mile run time, and after 4 years of HRT, no statistical difference in sit-up performance. Thus if any individual trans woman outperforms a cis woman, that outperformance is likely within the range of typical variability already present among cis women. These studies are likely just the tip of the iceberg in this still-new field of research on trans athletes.

Sports already accommodate greater variation among cis members of the same sex than might exist between a trans and cis athlete. In football, athletes with different body compositions have advantages at playing different positions. Running backs are smaller than offensive linemen because they need more mobility to duck blocks and sprint on the open field. Offensive linemen are large, to protect these smaller players, often at the expense of their speed and mobility. Hockey operates on a series of “codes”, enforced by players, to try to make inevitable physical contact between players fairer and to prevent injury. Weight classes in wrestling and boxing level the playing field between competitors. Karate competitions are organized by skill level, belt color, not gender. People have solved the question of fairness many times before. There deserves to be a good faith discussion about what fairness in professional sports means, if sports should be gender-segregated, and more. But that’s clearly not the aim of the “debate” instigated by the right.

Youth sports are crucial to the social and physical development of children and teens. Most youth sports are not competitive in a professional sense until after puberty and many sports remain coed until then. Prepubescent children have similar athletic performance regardless of sex. New proposed bans on trans athletes include elementary school level bans, but there is no evidence that trans participation makes youth sports any more dangerous or less “fair”. Subjecting children to sex testing in order to play is cruel and ripe for abuse. The anti-trans frenzy means girls are being interrogated for having short hair or early growth spurts, experiences that will only discourage kids, both cis and trans, from participating in sports. This is about socially isolating trans kids and denying them the benefits of sports.

Why Is This Such A Big Part Of The Culture War?

Right-wing culture warriors have latched on to the issue of trans women in sports because this conversation is nuanced, and the biology is barely understood by the public. Both corporate parties promote the narrative that trans people are unsafe in women’s spaces despite the complete lack of evidence for this. Instead of facing real issues in women’s sports, like underfunding, abuse, and toxic self-harm cultures, these ghouls point the finger at an already extremely marginalized minority. They want to push trans people back into the closet, to restrict bodily autonomy, and to narrow the definition of “woman” and “man”. They want a return to “traditional” gender roles and the “nuclear family” which historically have been used to keep a patriotic capitalist society humming. They rely on division to keep workers fighting for scraps.

Any coach will tell you that what separates a champion from others with athletic skill is mentality, a voracious determination to not only overcome obstacles, but to face them head on. Human sex characteristics won’t tell you which athlete has drive, focus, dedication, access to training resources, or the economic stability to play. We can celebrate people who excel at their sport, but this does not encompass all of what sports mean in our society. Sports are about companionship and teamwork. Teamwork trains workers to overcome divisions and build solidarity. 

The answer to this problem is not further exclusion, but to fight together for the betterment of society as a whole—a key part of that being creating space and funding for programs that allow everyone to enjoy athletics and sports culture.