I dont see the downfall of the Usa or western led world order anytime soon. Usa is not alone, it is Usa Canada many American nations, EU, GCC, Japan, Australia, S Korea, even india to some extent, they control most of the world economy and military power. Even Russia and China are unable to challenge them never mind anyone else crossing them. Example the war in Ukraine, Usa and EU openly arming Ukraine meanwhile Russia still cannot/unable to defend their Iran ally in the middleeast, China is close enough to a superpower but if they go against western led world order they will face collective nations as mentioned above. But the western led order does look after China aswell, after Saddam removal China still trades with Iraq total 17B exports v 33B imports, if Iranian regime is changed the Chinese interests will be looked after. Saudia Pakistan Turkey pact is no threat to the Usa, its aim is to protect Saudia and even Usa has done this for decades. GCC and Israel want the end of the Iranian regime, this will make Usa led world order more strong.
Keep in mind, within this world order alliance, nations have their own interests aswell, like in the middleeast.