Originally published in 1918, this book is a primer of the principles of peace. The author urges that the Pact of Locarno involves a risk graver than this country ought to sustain. He attempts to demonstrate that the only effective method of providing against future wars is a covenant for mutual assistance, to an agreed extent, in maintaining peace under the League of Nations, conditional upon the disarmament of each Power down to the limit of the forces necessary for the fulfilment of this covenant and for the purposes of internal order.