Jesus Christ. It's been twelve freaking years since this series debuted. We're also twelve books into it (plus one collection of short stories by mostly-other authors set in this universe). Annnd, as my review of _last_ year's entry, The Golden Princess, showed, I struggle with why I'm still reading this series.
So I'm not going to spend much time on this save to say: it's better than the last book was. We get action, the plot moves forward quite a bit, we get to find out what happened to the greater LA area after The Change… it's a decent entry in a series that probably should have been put to bed two arcs ago.
I'm not entirely sure why I'm still reading it save for the fact that Stirling _can_ knit a yarn pretty goddamned well, and I'm juuuuust enough of a sucker for "oh, we get to find out what happened to THAT part of the world after the Big Disaster?" that I'll put aside my inherent disdain for the increasing magical elements of this tale and bull through just for that.
Stirling is very, very good at creating and writing about alternate versions of our world (his Draka books remain my second-favorite type of this genre, juuuust barely beat-out by the downright depressing and therefore all-too-believable agonies of John Barnes' Century Next Door series…), and injects just enough of that into these books at this point to keep me grimly reading along, regardless of how many orbits my eyes have to do in their sockets at times when the fuckin' McClintocks and McKenzie's have to argue over the trivial differences between their fake-ass dipshit clans for the 79th time…
Fortunately, The Desert and the Blade is a lot better than The Golden Princess was, given that Things Actually Happen in this entry. The High Princess' Quest is in full flower, and they get through a good chunk of it. Stirling seems to have realized that part of the draw of this series was finding out what's going on elsewhere on our post-Change globe, so he introduces some characters who have had reason to travel that globe, and therefore can spend entire chapters describing what happened elsewhere. It's a fun, showy example of just how good Stirling is at world-building, and I appreciate the appearances here.
I can't give much more detail without giving away reasons to actually read this thing, and I assume anyone even considering it is already familiar with the world because good fuckin' luck jumping in on Vol. 12 if you aren't. In a world where this type of book has been almost entirely taken over by Young Adult tropes (bleaugh), I appreciate that Stirling is still writing somewhat more adult tales of the apocalypse, his staunch advocacy of Renn Faire nonsense aside. It's far from his best book, but certainly the best this series has seen for a while, and further sets up the next entry to be pretty far-ranging and interesting to my particular tastes.
So, if you're into this series already, you'll probably like this. If you're not, this book will probably just confuse you. If you like to spend your weekends m'ladying your way through Society for Creative Anachronism meetings, who are we kidding, you've probably already written erotic fanfic based on this world.