man outside the supermarket. He was not someone I knew but he apparently knew me because he wanted me to write a letter. He knew what he wanted me to say too.
He wanted me to say we should never have become involved in Iraq or Afghanistan - or indeed anywhere else. We should not, he told me, do anything to help Syrian refugees - or indeed help any refugees at all. Charity, he told me, begins at home and there was enough money wasted here anyway. People should, he informed me, look after themselves.
His verbal onslaught was so fast and furious I was given no opportunity to respond. It would have been useless anyway. He is, almost certainly, not the sort of person to listen to me - or to anyone else.
There have been other suggestions we should not get involved in the situation in Iraq again - in any way. It's dangerous. We are putting lives at risk.
Yes, it is dangerous. Yes, it will put lives at risk.
The problem is that there is a complex humanitarian emergency in Iraq and it is a problem that spills over the borders of Iraq into other places as well. It is a far worse problem than the media has suggested, perhaps worse than even those who do know something about the realities of what is happening there want to recognise.
And, for me, the problem of whether we help or not is simple. We have to help. It is our duty and our responsibility to help the very elderly, the women and the very young trapped on Mt Sinjar and in like circumstances elsewhere - not just in Iraq but in other places as well.
The man who accosted me said that they did not need help. They looked well fed and well dressed. Most of them were not crying - "just a few silly women and a couple of spoilt kids". He completely ignored the fact that these people have fled their homes, often with nothing at all. They have not changed their clothes for days. They haven't had a bath. They have no shelter. They sleep, if they sleep at all, in the open. It is cold at night and hot during the day. They have reached that point where they cannot cry because emotions take energy they simply do not have. If he looked closely he would see the children are not playing. They stay close to the adults who are left - and the expression in their eyes says more than I want to read but I doubt he could see it.
He told me that they didn't look hungry either - that when some of them were given a meal they weren't bolting it down as if they were starving. No, it reaches a point where you wonder where the next meal is coming from and whether you should save this one just a little bit longer in case there isn't another meal or keep it to feed your children and go without yourself.
And there are times when there is nothing you can do about the situation you find yourself in. You have to rely on other people.
And some of those people have to be us - however difficult and dangerous it might be.