You can still hide an explosive under the Turban
It still conceals features that can be used to identify a person, like hair type.
I am not just talking about showing face. Showing face is mandatory at all airports including in Muslim countries, but head scarves have been taken off as well and in some case the entire Abaya.
The scanning machines can see through the turban to find a knife, for example. The radiation counter check will find a bomb within a turban. In this particular incident, it is reasonable to ask the Romans to show the due respect and find means to complete their security check without having to remove the turban. And, if all else fails, at least make provision for the turban to be removed in a private room. As a Sikh, it is our responsibility to educate those unaware, that removing the turban is no less than removing our clothes. It is not a hat. It is a deeply respected religious symbol. Sure, they may disregard our concerns and continue to show disrespect. But, remember, that also means they lose the privilege of being called educated, civil, and human.
Sikhs wear turban because our 10th ( and last ) Guru , Guru Gobind Singh told us to look distinct as his sons and daughters . Guru Gobind Singh himself wore a turban and since he is the Guru ( Prophet ) of Sikhs , it is considered important that followers look like prophet ( to follow him ) . "The turban is our Guru's gift to us. It is how we crown ourselves as the Singhs and Kaurs who sit on the throne of commitment to our own higher consciousness. For men and women alike, this projective identity conveys royalty, grace, and uniqueness. It is a signal to others that we live in the image of Infinity and are dedicated to serving all. The turban doesn't represent anything except complete commitment. When you choose to stand out by tying your turban, you stand fearlessly as one single person standing out from six billion people. It is a most outstanding act."
"Speaking to TOI over phone, Singh described the attitude of the security personnel at Rome airport as insensitive. He said when the staff asked him to remove his turban, he tried to tell them that this was not possible as it defied the teachings of Sikhism.
"But they refused to understand. We even offered that the staff could touch the turban on the head and run a metal detector over it to ensure that security was compromised. But they refused and did not allow us to take the flight," Singh said.
"We have reported the matter to the Indian embassy in Rome. There are around 40 gurdwaras in Italy and we were here to attend the International Sikh Dastar (Turban) Awareness Day at the invitation of the Sikh Channel (UK) at Cremona," he added.
A statement issued by DSGMC office in Delhi quoted Singh: "The Indian embassy in Rome intervened with the local officials and airport administration at the highest level but their efforts were unsuccessful. The Italian embassy in New Delhi and the Indian embassy in Rome had been informed about the visit of this delegation to Italy," Singh said.
The Italians insisted on removing the turbans despite having accepted it as a religious symbol in 2011. Italy had at that time declared that Sikhs will not have to remove their turbans at airports for security screening, after strong protests by Sikhs and the Indian government."
Sikh delegation told to remove turbans at Rome airport - Times Of India