Blood, Iron & Gold is an international history of how the railways shaped society, economies, and even our sense of time. Starting with the earliest simple services, Wolmar weaves a story around how the railway collapsed distances and created nations.
The first three quarters of the book are on the first century of the railway, when much of the international network was built and almost all changes were progress. There is an accounting of the deaths involved in building our railways, and how they were used to control empires, as well as unite countries on a fair footing.
But the story after the start of World War One is more complex. For the first time, the railways are essential in how a war was fought, with rail-based troop transport and supply being vital to the continuation of trench warfare, with all the pointless death involved.
Then afterwards, the decline in patronage, continuing to late in the twentieth century. Wolmar is more sympathetic to the cause of the reduction in lines than might be expected though. He accepts that some of the railway mania had led to excessive construction, and that a sustainable network required some reduction.
It helps that he manges to end on the high note of the twenty-first century rain renaissance, with congestion making the train yet again an attractive mode.