I thought Pete M would know about the blue light. The strawing line, I think, means that the best of our young men have been scattered in the sea, stirred by, or stirring the weeds. Or, indeed, the best of many nations. i was appalled when I chanced across the merchant navy memorial near the Tower of London, a long wall of names, the name of each ship, followed by the names of its crew, and so many of them from the colonies. I don't know the date of the poem, but it has the sadness of the man who lost his children.