This is book 2 of The Themis Files.
I enjoyed the first book enough to read the second book, and this was the second book. It starts about a decade after the last one ended, where everyone has pretty much become used to having a large (like 200' large), alien robot hanging out on the world doing book readings and press conferences.
And then another robot shows up and starts killing everyone.
The book moved at a more frenetic pace than the first one did, which is reasonable given the first one needed to world-build and this one can coast along on those words. Not everyone dies in the end, and we don't see enough of the characters we saw in the first one, and the rough edges have been smoothed off everyone's personality, all which contributed to this being a typical sophomoric book: less good than the first, but sufficient.
There's one more book in the series, coming out in May, which I'll read. I think this book is better experienced on audiobook, to be honest.
Military people — people like me — need intelligence to be useful. We need to know what’s going on. Without intelligence, take my word for it, you do not want your fate in the hands of the military. We do not improvise.
Scientists are like children: They always want to know everything, they all ask too many questions, and they never follow orders to the letter.
— Do you remember what you told me the second time around to get me to take this job?
— I do.
— You said: “I found you a military post where you’ll never have to kill anyone ever again.”