I don't consider the US 'the west', but if you want to pick favorites based on body count, I'd be willing to bet China still loses given the red army and the great famine that birthed it's current dictatorship.
If you're counting deaths caused by unintended consequences of poor policy, one could argue that the west also is to blame for tragedies like the Great Famine because the policies that caused it were born from reactions to Western hegemony from the previous centuries.
Then you have to blame the countries themselves for allowing western hegemony. Poor policies are to blame for a small population of foreign actors being able to wield so much power over those regions.
I think we have to judge a thing on its actions, or the arguments get rather circular.
There is no Qing emperor to blame anymore for allowing China to stagnate and losing the Opium Wars. Meanwhile, the same governments who used forced projection to coerce China into allowing the import of Opium are continuing to abuse force projection to this day.
They are only the same governments insofar as there have been no total revolutions. The people, laws, morals, and even constitution in the UK are different today than during the opium wars. Probably as much so as the CCP differs from the Qing.
The governments may have changed to a certain degree but not when it comes to geopolitics. It took CCP two years to figure out that bad agricultural science was bad. How many wars will it take for Americans to factor the impact of asymmetric warfare on residents into their calculus of whether to go to war?
Wait… are you saying it’s the colonized indigenous peoples fault that they were exploited and oppressed by their oppressors?
No, I'm saying the great famine is no more Britain's fault than the opium wars are the Chinese people's fault.
The only thing we did wrong in Bosnia was not stopping the genocide sooner.