I had the most interesting conversation with my neighbor today while we were chipping away at ice still blocking the corners of our blocks after that storm of a couple weeks ago. He's Indian-American who works in some military medical projects he couldn't discuss. He brought up that China attacked India while the Soviets were distracted by the Cuban Missile crisis. The Soviets had a tenuous alliance with India and were starting to dislike (Khrushchev and Mao were oil and water) the direction of the PRC. He said that he worries that Iran will be the distraction for us that might give Xi (who just got rid of the one person in Zhang Youxia telling him not to attack Taiwan) the chance to attack Taiwan.
We were talking about arms control being an impossibility in a situation in which nobody trusts each other and there are no efforts to have confidence-building. To Trump, to Putin its all gangsterism. Xi might be willing to sign up to a rules-based order but nobody can trust the order if more than one of the lynch pins is totally unreliable.