The Germans were then believed to have planned to overrun the Netherlands and use Dutch airfields to launch a bombing campaign meant to achieve a knockout blow against Britain, and raze British cities to the ground. The French attitude towards a German invasion of the Netherlands was crucial because France was the only country in Western Europe that possessed an army large enough and modern enough to save the Dutch. Moreover, the importance of France to British security had increased following a violent anti-British propaganda campaign launched in Germany in November 1938, which had led the Chamberlain government to perceive German foreign policy as anti-British. This scare was combined with rumours that Bonnet was secretly attempting to negotiate a Franco-German "special relationship" that might leave Britain facing a hostile Germany without any allies who possessed the large armies that Britain lacked. In response to Phipps's message, Bonnet had Charles Corbin, the French ambassador in London, inform Lord Halifax that the French attitude towards German aggression towards the Netherlands would depend upon what the British attitude towards France was if the latter were the victim of aggression. Chamberlain stated to the House of Commons on 6 February 1939 that any German attack on France would automatically be considered an attack on Britain, thereby leading the British to make the "continental commitment" to send a large army to the defense of France that successive French diplomats had struggled to obtain since 1919.