The execution of monarch is always legally suspect and it is folly to execute one on such grounds, it is folly to execute any head of state. The executioners will always be much worse, what did France gain out of the revolution? Some good, the memeory of Republic, but what was that memory for most people in Europe, the Frencg included? Tyranny, bloodthirsty nationalism and brutal war, the French revolution is the perfect example of how not to conduct a revolution.
The idea that you must commit large numbers of state sanctioned murders in order to attain freedom, is reprehensible and not worthy of emulation. Surely you agree with this?