From travelling in the EU passport control on landing in a country is normally a short and painless final obstacle between you and the exciting new country across the imaginary line marking the border.

The USA is as we are to find with many things, very different. Two hours of queuing led us to a border guard who as well as taking all our finger prints (I doubt anywhere in the uk exists a record of Archie and my finger prints) grilled us on every detail on our trip. Despite having nothing to hide it was hard not to feel an odd sense of guilt that we must have done something wrong. But with a warm and welcoming "you're done here" we were through and the trip began.