Does anyone in China believe Trump is actually calling the shots in his administration? Or that he's capable of following through on anything?
I'll also point out that for all Trump's whining that diplomacy doesn't work, he has never actually engaged in any.
If the goal is to denuclearize North Korea, Trump's probably right that diplomacy won't work - there's really way it's in the self-interest of the North Korean regime to give up their nuclear weapons and tbh it's not like they negotiate in good faith anyway. The more pertinent question now is whether we're willing to live with the status quo of North Korea having nuclear weapons which can hit the US. Not that I think Trump has handled this well and I don't have faith in him doing the right thing, but it's not his fault that we're at a point where we're choosing between a very bad situation and an absolutely awful one.
Kim doesn't want to end up like Saddam Hussein. They will NEVER give up their nukes. Also, we already live under the Chinese, Russian, and Pakistani nuclear threats. We should just isolate that regime, cut all trade, and leave them to rot alone. America will be fine.