The Ruhr occupation of 1923-1925 marked a shift in the balance of power in Europe in Germany's favour. Firstly, it demonstrated that the Anglo-French entente had ended as a counter-weight to German power. Secondly, France was faced with a united front of Germany-Britain-America against its invasion and was denounced as a chauvinistic, warmongering, greedy power. Politicians and the press in Britain, for example, regarded the French view that Germany was preparing to launch another war as absurd and "insane" (in the words of Balfour).

Although the Ruhr occupation was profitable, the furore it caused shattered French will. As the historian Sir Denis Brogan wrote: "Germany was still open to French invasion, but the will to invade was dead". So by the 1930s when Germany managed not only to get reparations abolished but was openly flouting the disarmament clauses of the Versailles Treaty, France did not feel able to act even when she possessed military superiority (until the late 30s). France was divided between right and left (who were anti-militarist); a divided country is not in an ideal state to invade another.

Source: D. W. Brogan, The Development of Modern France (1870-1939) (London: Hamish Hamilton, 1945).