To avoid a struggle with England was well-nigh impossible; but what France might have done, and did not, was to remain faithful to the alliance with Prussia, instead of plunging into one absolutely contrary to every tradition of its foreign policy, the Austrian alliance. What the diplomacy of Louis XV. lacked was consecutiveness. The versatile monarch did not know what he wanted. Sometimes Prussian, sometimes Austrian, he fluctuated between two contradictory systems. The see-saw policy creates only a momentary illusion. It succeeds for a while, but it nearly always leads to ruin. The secret of strong diplomatists is to persevere in one idea, pursue one end, choose one good alliance, and stick to it. Feeble diplomatists, on the contrary, undo to-day what they did yesterday. It is like the web of Penelope. Whoever studies seriously the causes of our reverses, under Napoleonic France as well as under the France of the Bourbons, will easily convince himself that nearly all of them are due to incoherent principles and inconsistent ideas. To preserve a system and follow a tradition gives a real strength. The strength of Prince Bismarck is to have persevered in one idea, that of German unity, and in one alliance, that of Russia. The policy of the Versailles treaty of 1756, which established an intimate accord between Louis XV. and Maria Theresa, was not in itself a more objectionable policy than another. But if it was desired to adopt it, it ought not to have been necessary to make war with Austria beforehand. Nothing is more dangerous than to place one’s self in a self-contradictory attitude. No confidence is inspired by such variable conduct; one is at the mercy of every incident. In politics, as in religion and literature, the prime essential is unity. It is the same thing in diplomacy as in style. “Ce que l’on conçoit bien s’énonce clairement, Et les mots pour le dire arrivent aisément.”[49] What is required is a true spirit of method, a clear, precise, definite object, straight lines, an absence of tortuous proceedings. The old maxim, “divide to reign,” the presence in the same ministry of men warring against each other, of secret agents who undo the work of official agents, underhand ways, countermines, politics by double entry,--all this is no sign of strength; it is the expedient of weakness. Occult diplomacy, like that of Louis XV., is suitable to none but governments in extremity. Woe to a sovereign who suspects his own ambassadors! If he has not full confidence in them, let him change them!