This note contains spoilers for the book.

Third in the series. Kris saves her home planet from invasion, against the wishes of the interim government that has displaced her father.

She gets to put the in-system defense boats that are being scrapped to work, and also ends up convincing a bunch of yacht crews and even owners to follow her (and a lot of them don't survive). This is the first book that's really deeply into naval leadership.

Definitely one of the better books in this series.

And they ain't aliens, despite several reviews floating around the net.