But with knee jerk reaction the WHOLE WORLD had to comply with security regulations imposed by the good old US of A!
Not correct. British security regulations were already well ahead of US regulations (due to experiences of Lockerbie, etc.) so did not suffer any 'knee jerk' reaction. If the 'good old US of A' wants to insist on regulations for flights into the 'good old US of A', that is entirely up to them. The 'WHOLE WORLD' can do what they like on their own... (But then maybe there is a threat out there and the 'WHOLE WORLD' is actually being sensible.)
But the problem here is the way crews are treated so very differently in different parts of the world. LHR obviously doesn't give any leeway so it is not surprising that on the odd occasion there will be someone 'caught out' doing what he/she might expect as being normal elsewhere. The problem is: Is common sense used when dealing with it, or is the 'miscreant' instantly treated as a criminal?