Isn't it amazing how this argument has done a screeching u-turn from "Johnson didn't mean to insult Muslims and really supports their wearing their traditional dress" - to " "Well really, these people are quite likely to be carrying bombs and weapons so they should be banned"

Polls on the subject of wearing the burka suggest 60% of voters support it's ban.
It is not traditional Islamic dress, it is the dress of a small(though increasing)minority.
To argue such people may be carrying guns or weapons is facile, and totally avoids the true issue.

Identification cannot be carried out while wearing a mask and similarly communications is restricted when facial expression cannot be read.
(The argument that caused controversy with jack straw and essentially the argument advanced by the )

There is also the element of trust. I feel uncomfortable being in the vicinity of masked people, they pose a potential threat that I have no way of quantifying. If people want to be in public places, I want to see their faces.

I suppose the arguments are a very good way of deflecting argument away from labour's civil war.