Baron Chazal, who had joined the Belgian ministry in 1857, succeeded in convincing the Cabinet of the necessity of reinforcing Belgian defences. In view of the superiority of the French army--for the threat came evidently from that quarter at the time--it was decided to give up the idea of defending the country by a cordon of inefficient fortresses, and to build round Antwerp a powerful "entrenched camp," where the Belgian army could retreat and maintain itself until reinforcements came from abroad. It goes without saying that the only country which would be in a position to send such reinforcements to Antwerp, in case of an invasion, was Great Britain, and Antwerp was purposely chosen as the only position where considerable forces could conveniently be disembarked from the sea. In view of the present interpretation placed on the 1839 treaties by Holland, which gives to the latter country the right to close the Scheldt in time of war, this scheme seems, to say the least, hastily conceived. But the Dutch exclusive sovereignty over the Scheldt did not appear nearly so definite at the time as it appears now. No mention being made of the matter in the 1839 settlement, many Belgian authorities considered that the stream was placed under a régime of co-sovereignty, and it seemed then incredible that the Dutch should stop the passage of relief ships.
In the face of strong popular opposition, the Chamber voted a credit of 50,000,000 francs for the Antwerp fortifications, and General Brialmont, one of the foremost military engineers in Europe, was entrusted with the work. After its completion, Antwerp was considered one of the strongest fortified towns in the world.
As soon as a conflict became imminent between France and Prussia, Great Britain, in accordance with her traditional policy as far as Belgium was concerned, demanded from the two Powers a declaration confirming Belgian neutrality. The situation in 1870 corresponds exactly to that in 1914, and the language used by Mr. Asquith during the first days of August of the latter year seems to echo the words uttered forty years before by his great chief. "It would be impossible for us not to interfere," firmly declared Mr. Gladstone, "should we witness the destruction of Belgium's liberty and independence." In both cases, British policy was inspired by the guarantee mentioned in the treaties, a guarantee which not only implied safety for Belgium, but also absolute opposition to any Power attempting to seize the Belgian coast. The motives were the same, the steps taken were the same, the outcome only was different. Both the French emperor and Bismarck confirmed, in 1870, the inviolability of Belgian territory, the latter stating that such a declaration was not required, the treaties being sufficiently explicit on the subject.