What is your opinion on the new fashion [in the Arab world] of people wearing caps with a visor in front [i.e., baseball caps]?
It is not permissible for a Muslim to imitate the kuffaar in
his dress. If wearing these caps or anything else is one of their
distinguishing features and something for which they are well are known and
by which they are distinguished from others, then it is not permissible for
the Muslim to wear those things. But if it serves some purpose and it is not
something that belongs exclusively to the kuffaar, such as hats worn for
work on building sites or in other workplaces, which are worn to protect the
head and shade the eyes from the sun, there is nothing wrong with doing
that. But if the hat is worn with the visor to the side or the back, this is
not appropriate for the Muslim youth.