"From" may be a bit strong: in the acknowledgements the authors mentions that the AEI gave him a grant so that he could afford to spend the time doing research. The author is/was also a fellow at:

* https://en.wikipedia.org/wiki/Hudson_Institute

This doesn't invalidate the outline of events that the book goes over, it just means that anything shown in a positive light may have been "too/more positive" and anything shown in a negative light could have been "too/more negative". Everyone has their biases.