Example 1 - third-generation Italian enthusiastically celebrating the English national football team losing.
Example 2 - proudly being British up until Andy Murray plays tennis, and then you're English, and you've formed an emotional alliance with *insert origin of opponent*
Example 3 - when arguing, we can't give foreign aid when we have people on food banks, having only just voted for austerity and cuts in welfare

A casual invitation / threat used by an individual that is not afraid of fucking someone up.