Responsibility is not so important. Had the USSR lost to Germany, the world would still have recognized Germany.I think China need to be VERY CRYSTAL CLEAR, that the responsibility for war fall entirely on the Stooges in the White House and the DPP, If China is not clear enough they could find themselves in a situation that the only option is total war and the absolute destruction of that island.
The US, especially the GOP, they like to use ambiguity to push around, like, "Peace Through Strength", "Status Quo" while the same time pushing the redlines backward towards their insidious goals, for the US Taiwan and the DPP are just disposable tools that they can use to covertly push the redline to whatever goal they want, they don't care about the economy of that island and their people as long serve their goals. I hope the Taiwanese could see this and push against the DPP before what took them decades to built is completely lost and destroyed in a matter of few years.
Training and readying a force that can crush would be invaders and counterinvade them is infinitely more important.
Regarding policy on US, there are only really two alternatives.
1. China's economic/diplomatic war succeeds in destroying NATO and the US empire is dissolved like the Soviet one was.
2. China doesn't manage to contain US with peaceful methods and has to go to war to halt US expansion.
Either way, if China wins, no one will question in terms of morals or responsibility. If by some divine intervention China can't beat an enemy that's weaker in pretty much every way, because US is an extreme expansionist state, they will probably demand China cede home territory like Taiwan. This obviously can't happen and there will be a nuclear MAD.