Even the most secular of Jews, who observe no other part of Judaism, almost always observe these laws. Of course, until quite recently, the majority of males in the United States were routinely circumcised, so this doesn't seem very surprising. But keep in mind that there is more to the ritual of the brit milah than merely the process of physically removing the foreskin, and many otherwise non-observant Jews observe the entire ritual. The covenant was originally made with Abraham . It is the first commandment specific to the Jews.
Circumcision is performed only on males.
It is also a sign that the Jewish people will be perpetuated through the circumcised man. The health benefits of this practice are merely incidental. It is worth noting, however, that circumcised males have a lower risk of certain cancers, and the sexual partners of circumcised males also have a lower risk of certain cancers. The commandment is binding upon both the father of the child and the child himself. If a father does not have his son circumcised, the son is obligated to have himself circumcised as soon as he becomes an adult.