""Balance of power" means only this—that a number of weaker States may unite to prevent a stronger one from acquiring a power which should be dangerous to them, and which should overthrow their independence, their liberty, and their freedom of action. It is the doctrine of self-preservation. It is the doctrine of self-defence, with the simple qualification that it is combined with sagacity and with forethought, and an endeavour to prevent imminent danger before it comes thundering at your doors."