I've been reading Roxanne Varzi's very interesting ethnography, Warring Souls: Youth, Media, and Martyrdom in Post-Revolutionary Iran, and came across this interesting bit:
When the meaning of sacred symbols shifts [such as the chador, conventionally worn by women who support the Islamic revolution, but now sometimes worn by young women out on dates with their boyfriends], power structures are renegotiated, as well as trust in one's own vision. An example is the Arab qafiyeh (scarf) [I have no idea why Varzi adopts such an idiosyncratic spelling]: a symbol of Palestinian resistance. The qafiyeh was first donned by Islamic revolutionaries to show support for Palestine and resistance to Westernization. Later, it became a symbol of the volunteer soldiers fighting for Islam in the Iran-Iraq war.
The qafiyeh is still worn by Ayatollah Khameini [Iran's current Supreme Leader and ex-president]. Just before the Iranian New Year in spring 2000, a hit man [Saeed Asgar] in the assassination attempt on the reformist Said Hajjarian was described as wearing a beard and a qafiyeh. Suddenly the symbol sacred to Islamic revolutionaries became descriptive of a suspect against reform. Hatamikia, a well-known film director, wrote an editorial reminding the nation that the qafiyeh is not the symbol of an assassin or murderer; and he added that it was disrespectful to emphasize this characteristic in the description of Hajjarian's would-be assassin.
Go here for a Middle East Report Online interview with Hajjarian. For another example of the shifting meaning of "sacred symbols" in Iran, go here to read about how the Islamic republic has banned the wearing of red kufiyas as badges of Arab identity in Khuzistan/'Arabistan.
The photos are of Ayatollah Khameini, one from the early eighties, the other contemporary.