Its extraordinarily interesting. I made a statement that was almost verbatim of your last sentence when I read about Cheney last week.
On the front of pondering WW3, it seems to be the case that WW3 is either going to pop off or it is not. If it does pop off, its not going to be because of the use of US weaponry. If it were hinged on proxy of US supplies, we would already be in WW3. Since we're not privy to Sec of Defense Austin's call with his Russian counterpart to lay out US response to nuclear escalation, nobody without security clearance knows what the line in the sand is, but clearly Russia has not crossed it.
With that in mind, the US supplying arms to Ukraine will apparently not be the cause of WW3. What will be the cause of WW3 is Russia executing its next steps beyond reclaiming the territory that is Ukraine, which seems painfully clear is their goal. From the 40,000 foot view, one could argue this was a war that was always going to happen since the stage was set when Russian did not withdraw from East Germany following WW2. And I tend to agree that General McArthur was of the correct opinion that the Allies, who were already primed and mobilized and possessed "the bomb" should have smashed the Red Army then and there and settled the matter once and for all. Some years later, Kennedy closely considered a preemptive strike when Russian did not yet have nuclear launch capabilities. A 2nd opportunity was missed to end this before it started. 80 years later, here we are and Russia is wasting its military away on a daily basis in addition to providing all of the intel about one's enemy that any adversary could possibly desire including the utter inability to do logistics or obtain air superiority. There is a perspective here that any reasonable person must entertain and that is that the US is getting a basement-bargain deal on letting Russia waste itself into being a non threat and possibly avoiding WW3 due to the severely weakened state that results.
Of course, there is no certainty in any of this and much information that none of us are privy to, but it seems clear that the US taking the position of isolation is not in anyway a guarantee of avoiding WW3 and it also seems clear, at least thus far, that the US supplying arms will not trigger WW3.
Yes, China wants Taiwan and they want it bad, but their economy is too tied to that of the US and, from a statistical standpoint, China's economic trajectory ends come 2040 due to their birthrate which cannot be corrected at this point. They simply will not have the labor force to proceed. So that kicks it back to Russia. I don't know exactly what outcome avoids WW3, but we do that the US supplying arms does not apparently trigger it and Russia rolling over the former block countries, some of whom will absolutely not go gently into the night will (looking at you, Poland), by default triggers WW3. IMHO, the best case scenario for avoiding WW3 is Russia losing the will to continue to fight and that only happens with weapons from the West.
That's my perspective on it. I don't know everything and I fully acknowledge that there are other perspectives and I'm willing to change my position as new information, developments and perspectives emerge.
The war machine denied a peace treaty 2 years ago between Russia and Ukraine.
Arms are one of our biggest exports, the military industrial complex must be fed.