As for Tienanmen, every single mob revolution in the history of the world has caused far more deaths than the number of people who died at Tienanmen. Imagine how many millions of lives would have been saved if Louis the XVI had acted in the same way as Deng. The Chinese government did the right thing in putting in forcefully dispersing the mob. Any government, when faced with a armed, violent rebellion, needs to put it down. Revolutions and civil wars are the worse than any government. (And yes, the protesters had weapons: http://www.amazon.com/gp/reader/0385482329/ref=sib_dp_srch_p... )
Had Louis XVI acted in the same way as Deng, continental Europe may still be under the heel of absolute monarchism today, with all the stupid pointless wars that entails. The French Revolution was a step forward for humanity, no matter how messy it was.
Gorbechev was fairly similar to Deng. He liberalized the economy and increased freedom of speech, but he did not allow democracy. Yeltsin introduced democracy, and what was the result? A terrible economy, a dramatic rise in suicide rates and alcoholism, and now under Putin, even speech is becoming less free. If only there could have been two Dengs, one for China and one for Russia!
The heel of monarchism? What heel? The fundamental problem of monarchy was not that it was oppressive (it wasn't), but that it wasn't a very good military Schelling point. Were taxes higher under monarchy? Was their less freedom of speech? Were there more wars? No, no, and no. Where do you get your history?
Look at the history of free speech for example. Pretty much every country that has gotten free speech, originally got free speech while under non-democratic government (Britain under the monarchy, France under Louis the XVI, U.S. under British Colonial rule, Germany under Allied military command, Japan under allied military command). Democracy has generally either been neutral or corrosive towards freedom ( the French Revolution, the terrorizing of the loyalists in America http://books.google.com/books?id=SZccAAAAMAAJ&printsec=f... , Nazis, etc ).
And pointless wars? The Wars of the French Revolution killed far, far more than any monarchist war. Not only that, they invented the usage of mass slave armies to fight the war. The French Revolution Wars and the Napoleonic Wars presaged the great Democratic total wars that followed - the Civil War, WWI, and WWII.
Had Louis the XVI put down the mob, the nationalization, conscript armies, and total war may have never been invented. Prussia would have never felt the need to unify to protect themselves against France. It's almost impossible to imagine World War I or World War II without the Wars of the French Revolution.
The British monarchy was a constitutional monarchy with almost all of the real power devolved to the nobles and the commons by the time of the French Revolution, quite unlike the French monarchy prior to the revolution. It's a fallacy to compare the two. The American revolution was an issue of home rule, not an issue of democracy vs. monarchy. And not the first such conflict the British Empire would face.
The Wars of the French Revolution were monarchist wars, waged to protect Europe's monarchs from the seeds of dissension spread from the revolution. So, technically, were the Napoleonic wars, as Napoleon was an emperor. However, the Napoleonic Code was a step forward for civil rights in Europe.
The aggressors in WWI and WWII were either monarchies or dictatorships: Germany under the Kaiser, Austia-Hungary under the Habsburg monarchy, the Ottomans under their monarchy, Germany and Italy under fascist dictatorships, and Japan under a monarchy. At best you can pin Nazi Germany under the banner of democracy, since the Nazis were technically elected to parliament (after their street thugs started the Reichstag fire and beat up all the opposition). But since the Nazis were outspoken detractors of the very idea of democracy, even that is a stretch.
I don't think you have a full understanding of just how messy the French Revolution was. Are you familiar with the war in the Vendee? http://en.wikipedia.org/wiki/War_in_the_Vendee
How about the Committee of Public Safety? http://en.wikipedia.org/wiki/Committee_of_Public_Safety
> The French Revolution was a step forward for humanity, no matter how messy it was.
(from http://news.ycombinator.com/item?id=868344)
The idea that the government should kill protesters might seem far too disrespectful of human life, but then, doesn't the word "messy" in the above quote evoke the same reaction?