I can't say this is a great surprise.
Me late Missus was from the 3rd world (albeit a "nice" bit) their problem is with machetes. Only a Knife? Bah! Her advice was make sure you have a good handle. Yer don't want it to break off after stabbing them only once. Cos' at that point they will be p#ssed with you. (I paraphrase). Good or bad? somethings just "are".
Looked like butter wouldn't melt etc (well, sometimes!). and perhaps not typical, but by no means unusual..........But the attitude
don't get left behind at passport control.....it also rubs off, if not always in actions.......but I can see how it would rub off / carry on in the right (wrong?) environment - whether that be in Timbuktu or Tooting.
Still, I am sure HMG have a plan..........
