Before a sports game in the USA the custom is to sing the national anthem. During the singing the custom is for the players to remove their caps and place it over their hearts. Is that permissible for a Jewish player? Does it make a difference if he wears a yarmulja underneath? Thanks
It is permitted to remove one’s cap.
The question here is whether this will be considered an issue of Chukas Ha-Goyim (going in the ways of non-Jews).
The Rema rules that Chukas Ha-Goyim only applies to matters of immodesty or for an unexplained reason (Yoreh De’ah 178:1; see also Iggros Moshe Yoreh De’ah 1:81).
According to the Chochmas Adam (89:1) the principle will also apply when non-Jews establish a practice in the service of their religion (even if it is mentioned in the Torah that Jews had a similar practice).
In this case, removing one’s cap is a show of respect. Although the origins of the practice might be religious (I’m not sure about this), it is recognized today as a universal demonstration of respect, and will therefore not involve Chukas Ha-Goyim.
Of course, one should keep one’s yarmulke on.