This is an odd short-story to catalogue.
Although ostensibly about Jane and Alex, that relationship isn't really central to this story. Instead, the tension is brought by Jane's recruitment of an old female suitor from Chicago. Basically the plot goes like this - Jane wants gun control to pass through the houses of the American government, but is stymied by a conservative republican senate. Liz (the Chicagoian) is the perfect person to weasel it past all its obstacles. Unfortunately Liz once carried a torch for Jane, and those feelings linger. Will she agree to come help the administration?
I state this is an odd short-story to catalogue because it genuinely is. There is no romance really - Liz's angst is the closest thing too it - and Alex and Jane are separated for much of the novel. But the plot described above genuinely feels beside the point. I think this short-story is more of the jelly bit between the two prior books and some future one - designed not to stand alone, but to introduce a character which can then be focused on without her introduction feeling abrupt. At present, without that hypothetical future novel, the story feels lopsided.
If you like Jane and Alex then you're going to be intrigued, but not satisfied by this story.