When Did the French Revolution Begin to Go Wrong?

Lots of revolutions in the news last year and more to come in 2017.  I predict Venezuela.  But so many of them go bad.  The template for revolution going bad is the French Revolution of the 1790's.  Here's a story about the execution of Louis XVI.  Then there's the murder of Murat.  Then the French Civil War began.  http://dld.bz/ft4Tf

Up to this point the killings could have been taken as the necessary actions to change an entrenched despotism.  But now it went to execution.  Then came the Reign of Terror.  What would have happened had the French Revolutionaries kept to the high road?