I mean, you might as well have said if China didn't go through the Cultural Revolution, it's economy and technology might have surpassed America's completely by now and Taiwan would've been reunited. Could've, should've, would've, didn't.
America DID get into those Mideast military adventures AND boggled the ability to get the spoils from those adventures. That's the reality.
This was highly unlikely since the conditions were not available to achieve this level of development for the Chinese at that time. This is a fantasy. I am talking about a hypothetical reality that is achievable. Since this is a matter of public policy, the Americans could very well have redesigned the entire global structure to remain relevant in the coming decades if they had the wisdom to understand the process of decline of a nation, they just had to have studied history.
One thing to note is that this short-sightedness of American statesmen would not have prevailed if they had really had the necessary competence to assess and study trends. For example, the Americans would have intervened in the Middle East even without the attack on the WTC. Some leaders of the Bush administration had already wanted to invade and defeat Iraq since the first Gulf War. The attacks of September 11, 2001, only facilitated these actions.
Before, we looked at the world of the Cold War and saw the interaction between the United States and the Soviet Union: one limited the other. These limitations no longer existed in the years following the Cold War. If there was effective opposition to American foreign policy, it came from within the United States; however, this opposition that had a voice was silenced.
The decline and fall of empires are complex phenomena, influenced by a variety of interconnected factors. The main reasons for an Empire to fall are:
Excessive expansion - The US could very well have reduced its role in the world by reassessing its military presence
Depletion of resources - Resources were diverted to the aforementioned purposes that only enrich those who are interconnected with this expansion
Rebellions and civil unrest - With the resources diverted, there are fewer resources left to effectively improve the social situation of its citizens, the example of the VA and homeless people
Advances of rivals - Here is the only factor that the Americans could not have avoided, could have delayed, but could not have prevented, but still, the advance of rivals could very well have been controlled if there had been a coherent proposal of policies, which has not been the case for three decades and remains the case inferred here.