Another important thing to remember is that from the US perspective, its Air Force and Navy would be doing a lot of the heavy lifting for striking targets.
This won't work in a China-US conflict in WestPac for the reasons below.
Their strategy would be to degrade or destroy their enemies capability to utilize UAS like Shaheed.
How can the US hope to hunt the launch trucks in mainland China?
The situation Russia finds itself with in Ukraine is not how China and the United States wish to fight a war. They purchase the high-end systems and in numbers to avoid that type of conflict.
There's a huge number of potential targets in mainland China (200k+? ), many deep in the Chinese interior. Plus consider the sheer density of air defence assets. You're looking at 150+ airbases in China.
In comparison, the US only has access to a handful of useful airbases which are too close to China, and a small number of carriers for striking at targets.
In an arms race, it is impossible for the US to buy enough long-range, high-end systems to win a conflict against China. Consider how China has a significantly larger economy in real terms, and is now matching or exceeding the US in terms of annual Naval and Air Force procurement. Also consider the USAF presentation with the example of a US hypersonic weapon being 20x more expensive than the Chinese equivalent.
In comparison, it is possible for China to pursue such a a high-end systems strategy because the potential target set (Taiwan, Korea and Japan) is far smaller and is within 1300km of mainland China. This is within range of airstrikes comprising heavyweight fighters such as the J-20, J-16, JH-7 and also the bombers. The Chinese Air Force would be aiming for air superiority over the Japanese Home Islands for example. Then UAS like Shaheed become far more useful. I think of them as JDAMs or SDBs that can fly to the target themselves.
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So in summary, the US shouldn't be wasting money on an air defence system which will easily be countered.