Could not disagree with you more except to agree China is indeed our major concern. However a resurgent Russian empire allied to China would be almost as problematic - particularly after absorbing Ukraine, its population, and its resources. Most importantly, Russia would become an enduring growing threat to our European interests, rather permanently becoming an ever more powerful smokescreen for China and its aspirations.
I am as conservative as anyone I know, but I am not a neo-isolationist. We are as imperial as ancient Rome - though ours is mercantile. History is replete with examples of what happens when empires forget to defend their borders. Ours do not run along the Rio Grand and Oceanic seaboards. Twice in the last century, due to "America First" movements we ignored events in Europe to our unimaginable cost in blood and treasure. The Trump wing of my party seems to have embraced that notion fully. Fortunately fully 2/3's of Republicans support our efforts in Ukraine.
I frankly think Trump has great instincts on many issues. He was the nominee of my party twice, and I supported him, however reluctantly, both times. I admire is efforts with respect to our economy and immigration. But I also think he has a great weakness. He has what seems to be an inability to separate personal animosity from what is in the interests of the country as a whole. Whether a twitter storm with someone that does not matter or personal anger with Zelensky's unwillingness to become a pawn in US domestic politics, he has an inability to look beyond the immediate squabble. With respect to Ukraine, I could not be more certain it is wrongheaded.
But to your other point, I would like to understand how the money laundering the Isolationists throw round so casually works in the current situation. Hunter Biden's influence peddling - sure. Type of thing has been going on forever, and unless a quid pro quo can be proven - not simply alleged - sadly it isn't even illegal. But having been both a fairly senior military officer and an appointed officer in one of the big three defense corporations please tell me how transferring excess materiel to Ukraine under Presidential draw down authority is a money laundering operation. Since I have personally never seen it, I would like to understand how you believe it works.
Cant argue with the way this administration handled Afghanistan - though I am just as confident Trump had it at least as wrong as well. Had we followed his timetable, the plan would have been essentially the same to meet time and troop constraints - just a few months earlier.