Book - We shall fight on the beaches

Histories again.  Two quiet different conflicts but both with one of our  European neighbours.  A very detailed setting out of the preparations taken in the UK against the threats of invasion, much of which can still be seen along the southern English coast in the form of old castle works and pillboxes.  I particularly enjoyed the telling of why defences were laid out in the the way they were, often second guessing the likely actions of our enemies built on intelligence gleaned from diverse sources.  It was ever so , as today the country sets up it's defences of a different nature against terrorist attacks..