What bookworm is saying is that it is part of 'situational awareness' which is, in general, a GOOD thing to have - for pilots, anyway. Our TCAS has made a huge difference to our interpretation of the airspace around us but it IS limited in scope.
If the USA do not want pilots in their airspace to have 'SA', that is their choice. It will not stop us asking.
CRR - you do not tell us which particular part of the control scene you are, but is it really SO difficult to keep us in the loop? We do not wish to know the other pilot's sock size or auntie's name, but a clue as to why we are turning/slowing/levelling what-have-you does actually help. EG - 'number 5 in traffic' when we have been kept high-speed/straight-line to ctr/fix by the previous sector does affect the way we do things and does not take long to say?
Just seen TIAC's post and again - I would say that a clue as to what lies ahead from you guys and girls does help a lot. 'Track miles' are another very useful tool which LGW inbounds at least are very good at - and saves us asking for those, too - and messing up the crossword