In truth, his sluggish but very persistent mind never saw quite clearly where dreams must give way to realities; or, as M.de Falloux phrased it, "He does not know the difference between dreaming and thinking[7]." Thus his policy showed an odd mixture of generous haziness and belated practicality.
[7] _Notes from a Diary, 1851-1872_, by Sir M.E.Grant Duff, vol.i.

p.
120.
Long study of his uncle's policy showed him, rightly enough, that it erred in trampling down the feeling of nationality in Germany and elsewhere.

The nephew resolved to avoid this mistake and to pose as the champion of the oppressed and divided peoples of Italy, Germany, Poland, and the Balkan Peninsula--a programme that promised to appeal to the ideal aspirations of the French, to embarrass the dynasties that had overthrown the first Napoleon, and to yield substantial gains for his nephew.

Certainly it did so in the case of Italy; his championship of the Roumanians also helped on the making of that interesting Principality (1861) and gained the good-will of Russia; but he speedily forfeited this by his wholly ineffective efforts on behalf of the Poles in 1863.

His great mistakes, however, were committed in and after the year 1863, when he plunged into Mexican politics with the chimerical aim of founding a Roman Catholic Empire in Central America, and favoured the rise of Prussia in connection with the Schleswig-Holstein question.