Guess this means we will have a civil war in China, Alex
About the ongoing arguments in China:
Some points to make:
-China did not have its period of isolationism under Kangxi OTL. It was only in Yong Zheng's reign (i'm preeeeetty sure this isn't how you spell it, but i forgot so i'll let it slip

) that the ports were all closed to european powers and they let themselves stagnate and fall behind.
-The Opium Wars had LOTS to do with the following taiping and boxer rebellion. The populace thought Qing lost the mandate of heaven due to the damn war, and also the opium ruined china's economy which led to unhappiness among the peasants.
-I don't see why a China that is open to westerners can't keep up in technology. AFAIK, they were considered very civilized by the 17th century Europe. Furthermore, from a military standpoint, their armies aren't that behind in technology. Military technology at that time didn't really advance that much anyway. The cannon didn't improve for a long time (China had european imported cannons too), and muskets were still sort of impractical back then. Battles usually consisted of Cannon fires, then a cavalry charge (in china anyway). China also modeled its navy after the europeans (somewhat, they still looked like junks

) in subduing Taiwan/Ming remnants, so naval wise they were on par as well.
-Sino-Japanese War: The general consensus/propaganda in China is that they had boats with more firepower, but due to corruption in bureaucratic decision making, didn't have the ammo for those battleship/dreadnoughts. Of course personally i think the higher mobility and torpedoe boats that Japan employed was the key reason for Chinese failure (See russo-japanese war).