But an additional motive actuated the diplomatists of 1839, viz., Belgium was henceforth to be the corner-stone supporting the structure commonly designated “the balance of power in Europe.”

An objection has been made to the validity of the treaty signed in London, viz., England herself did not consider it reliable and binding, or she would not have asked for, and obtained, pledges from both Prussia and France to respect Belgian neutrality in 1870.  Another objection is the claim that the German Empire, founded in 1870, was not bound by the Prussian signature attached to a treaty in 1839.  Other writers have endeavoured to show that the addition of African territory (Congo Free State) to Belgium changed the political status of that country, exposed it to colonial conflicts with two great colonial Powers, and thus tacitly ended the state of neutrality.

Each of the professors in question overrides these objections, and Frank remarks, p. 13:  “Lawyers and diplomatists refuse, and rightly so, to accept this view.”  Again, p. 14.:  “There is no international document in existence which has cancelled Belgian neutrality.”

Germany’s alleged violation of her promise to regard Belgium as a neutral country is justified on quite other grounds.  Belgium had herself violated her neutrality by a secret alliance with France and England.  Frank argues that a neutral State has certain duties imposed upon it in peace time, and in support of his contention quotes Professor Arendt (Louvain University, 1845), who wrote:  “A neutral State may not conclude an alliance of defence and offence, by which in case of war between two other States it is pledged to help one of them.  Yet it is free and possesses the right to form alliances to protect its neutrality and in its own defence, but such defensive alliances can only be concluded after the outbreak of war.”

Another authority quoted to support his point is Professor Hilty (University of Bern, 1889).  “A neutral State may not conclude a treaty in advance to protect its own neutrality, because by this means a protectorate relationship would be created.”

Frank continues (p. 21):  “Hence Belgian neutrality was guaranteed in the interests of the balance of power in Europe, and I have already pointed out that the same idea prevailed when the barrier-systems of 1815 and 1818 were established.

“Considering the matter from this point of view, the falsity of modern Belgium’s interpretation at once becomes apparent.  According to Belgian official opinion her neutrality obligations only came into force in the event of war, and therefore could not be violated during peace.  But this balance of power was to be maintained, above all in time of peace, and might not be disturbed by any peaceful negotiations whatever, especially if these were calculated to manifest themselves in either advantageous or prejudicial form, in the event of war.