That would be a bad assumption then because historically what happened was China built multiple airbase with 3000 m runways capable of hosting strategic aircraft as they watched and did nothing, all within the past 10 years.True, but the US is also playing a game of tripwire. That’s why they are conducting FONOPS in a near weekly basis, whilst try to have at least one carrier battle group (ideally two) deployed in the region. One could argue that should China decide to strike, these CGs would be decimated by ASBMs. However, I think one should not underestimate how much defence planners in the US doubt CCP’s resolve. Many in Washington still believe that regardless how modernised the PLA has become, the CCP would not dare to start a war with the US, so the game of tripwire and salami slicing works so long as the PLA does not bite. And PH’s recent provocations in Huangyan/Scarborough demonstrate exactly such questioning of the PLA’s resolve and believe that China is so bogged down by its own economic ills and domestic social contradictions that Beijing is a paper tiger so long as the US does not try to directly overthrown the Party’s rule. This is also why Biden is even more aggressive than Trump and his team when dealing with China.
If they believed China was a paper tiger they could've rammed the dredging ships and dared China to do something about it in 2009. Did they? Well, the islands are there.