The mainstream debate about social constructs shows how deeply engrained individualism is in the American psyche. From an individualist viewpoint, there are two categories that a claim to knowledge can fall into: objective (existing “out there” in the real world) or subjective (all in your head). The concept of a social construct points toward a third option: human creations that are bigger than any individual’s arbitrary decisions.
A good example of this is the English language, which was created over many centuries by millions and millions of people. It is not a fact of nature in the same sense as the diameter of the Earth or the speed of light, but neither is it “all in my head.” It is something that is socially shared, and any changes in it come about not, for instance, because I up and decide to make up a word, but because a critical mass of other people adopt it.
Similarly, the legal code of the United States is not an objective fact in the same sense as the structure of DNA, but that doesn’t mean it’s “all in my head.” I can’t up and decide what is or isn’t legal, and in fact the only way to change the law is by following legal procedures. We might say that in certain exceptional circumstances, a judge decides what the law is — but that decision needs to be accepted by the broader judicial system to have the force of law in more than a temporary sense.
These concepts are incredibly simple. If anyone stopped and thought for a few minutes, they could grasp the meaning of a social construct. Even controversial claims such as “gender is a social construct” would make sense. Every society has had different gender roles, which it enforces in different ways. No one individual gets to decide what those roles are, and even if we concede that identifying someone’s gender is pretty straightforward in 95% of cases, there is still an element of recognition required.
Trans people may seem to be a special case, but they aren’t arbitrarily choosing their gender identity — they are (mostly) claiming that they can’t help but identify with a gender identity that does not match their biological sex, and they seek social recognition of that need (as well as medical treatment to help align their biology with their deeply felt gender identity). No one would make this request lightly, as shown by the scorn, derision, and even disgust that it arouses in many people. If it were possible to arbitrarily choose one’s gender identity, then trans people would have had every incentive to choose the “correct” one. We are dealing with something like an objective fact about the person’s psychological and physiological make-up and how it relates to a social construct — at no point is it a question of an individual just arbitrarily choosing to make something up.
In short, a social construct is social, meaning that it cannot be changed by an arbitrary individual choice. Social constructs can change, but only by social means — whether that is a vague social consensus (as in the inclusion of new words in the English language) or by explicitly codified means (as in legal systems). And the fact that this concept is so hard for most Americans to grasp is in fact evidence of an aggressive social construction of an artificial individualism — which unfortunately, I cannot change by arbitrary fiat, or else I totally would.