Summer of 1989, late one Saturday afternoon I was sat on the Tube heading back home to Tottenham. It's unusually quiet and there's only 2 of us in the carriage, both minding our own business - me and a black teenage kid and we're separated by the main door / open area bit, maybe 4 or 5 seats on top of that and we're on opposite sides of the carriage.
Anyway, the train approaches the next station and in a manner that I doubt I need to explain on a football forum you could just feel / hear the trouble coming. The train stops and probably 12-15 late teen / early 20s lads get on, already chanting "There ain't no black in the Union Jack". They spy my carriage-mate and as soon as the door closes immediately stand around him singing it over and over again, as well as swinging from the overhead hand loop things and monkey-chanting.
Anyway, I wanted with every part of me to have the balls to go and sit next to him, but I just sat where I was. Thinking about if if I had it might have made it worse insofar as however intimidating they were they never touched him and if I had moved it might have properly kicked off and we'd probably both have had the **** kicked out of us, but he wouldn't have been quite so alone and I still regret not doing it.