You write, "Invasion of Silesia was a singular order by Frederick II, was he enlightened king blessed by divine grace, or a bloodthirsty dictator ?"
Well, since I, usually take the Austrian view of things, bloodthirsty dictator does jump to mind. N. made Fredrick the Great look like a nothing.
You write, "War against France in 1805 was a singular decision of Alexandre I (see E.Sokolov, Austerlitz), was he little father of his peoples or a parricid usurpator ?"
Can't recall ever saying a nice thing about any Romanov. I do like that A. was willing to fund the experimental air ship; shows imagination. I also like that he knew exactly how to defend his country against the forces of N. I also like his guts and determination. Unlike the Habsburgs, there was no peacemaking when foreign forces were on their sacred soil. He also knew that the trick was to get N. to stay as long as possible in Moscow; so that nature could take it's course. Note: When Stalin was congratulated on entering Berlin, he commented that Alexander made it to Paris. Other than that, the Romanov's generally were repugnant people.
You write, "War against France in 1756 started by the capture in peace time of french merchant ships, by order of King Georges, was he a Gracious King or a trustless pirate ?"
trustless pirate, of course! It's even written in the Declaration of Independence. King George! Are you kidding?
You write, "Napoleon used to the full the institutions he inherited or created, and had ultimate decision on peace and war. But this was the case of any crowned head of the period, including UK."
Basically, your assertion is that N.'s actions are comparable to the actions of some of the most useless scum on the earth. My only disagreement depends perhaps on the scale of what it is that N. did.
A better comparison might be made of Joseph II and the last Austro-Turkish war in 1788-1790. The only real deference being that the Turks and Habsburgs were ancient enemies with a long history. Nobody can rightfully say that Russia and France were natural enemies; as I recall N. said something to that effect at Tilsit.
N.'s decision to invade Russia stands out as one of the most deadly in history and as I read it (Caulaincourt), mostly as a result of N.'s personal arrogance. Invading Russia in 1812 was one of the single worst decisions in history and it was made for the worst of reasons and N. holds sole responsibility for it.