Context:

Andrew Preston mentions his own book about the religious influence on American war and diplomacy, explaining that the title reflects the two main impulses in American Crusades - the aggressive 'sword of the spirit' and the more pacifistic 'shield of faith'.

Context:

Dominic introduces Professor Andrew Preston and mentions this book as the result of his extensive research project on the interface between religion and war in American history, describing Preston as 'a top historian of American religion and foreign policy.'