Individual distance

When I was a young zoology student we learned about fairly simple concepts, such as individual distance; the distance from an individual at which the presence of another individual of the same species incites aggression or avoidance. 

We are currently living in some trepidation that the citizens of America might actually elect Trump as their leader. Just in case that nightmare should come to fruition we are busy building a wall (see the "extra"), a big, big wall made from muckle lumps of best Aberdeenshire granite. That should keep The Donald at arm's length and protect our precious individual distances!