I do have to agree with the OP on this one, it is really easy to think logically behind your desk without someone yelling in your face. I would have moved to defuse first. How I wold have done that, who knows. But I can give you every assurance that it would not have included a law lecture about how I have the right to photograph her kids at will - even if I were completely in the right. It is not the place, time or the right conditions to have that discussion, nor would she have been receptive, no matter your verbal skills of persuasion.
To sit back here, and presume any of us could fully grasp the situation, and what we would have done, is silly. The media has scared the heck out of everyone in the UK. And to try to talk down a mama bear that her fears aren't justified... not a good battle to pick.
Those of you married I am sure have apologized for things you were not in the wrong for, because the bigger picture out weighs the individual battle. Getting defensive only makes you look more guilty. I wish I can say I would have dealt with the situation much differently and now the lady and I are best friends... who knows. But we can all learn from this and come up with our own strategies going forward so when this happens to you, and it will, ou know how you will deal with it. Thank heavens it wasn't their dad who had just perhaps had a few pints too many...
Don't think you know how you would have handled it... until you've been there, you don't know.