Arlington (The New Century Multiverse)

How would you change America?
This story takes place in 1883, the year Vice President Rutherford B. Hayes was eaten by a manticore.
With President Grant's health failing the race is on to find a replacement before the country is left without a leader, and to uncover the conspirators behind the assassination. Interested and dangerous people are closing in, sensing an imminent power-vacuum and the chance to seize control.
Thomas and Sarah Arlington are the directors of the first National Intelligence Agency in a shattered alternate history Washington DC. They face a dark, unavoidable streak of prejudice in the American psyche, and every decision, no matter how shrewdly considered, is met with opposition.
Can the Arlingtons, their twin daughters and the agents who work for them overcome their own anger, fear, naivety and obsession long enough to hold together the threads of what civilization has been recovered, or will what remains of humanity tumble into the abyss of frantic survival?