China should always aim to totally decimate and dismantle any threat. Doesn't matter if China allegedly leads in the numbers by 2030. Facts are: China has to expant even more so on those numbers. Having an "edge" is not enough. The enemy forces need to understand that only "supreme" and pure massacre awaits them if they go against China.
Think how the so-called "Western" -in essence - Imperial forces from 1800s think. It is as follows: Any country that can resist is considered a "threat".
It is insane just by the fact that U.S. thinks it can just send destroyers in the strait. Imagine PLA Navy just sending destroyers precisely outside Louisiana and Mississippi, just to irritate Orange Dumpsters, then visiting Mexico and Cuba, and putting some forces in Havana as well.
For far too long, its been normalized that Imperial forces can just have ships outside China's coast. China needs to also make it clear that Chinese reaction will be different to that of Russia and Iran.
While Russia and Iran have experienced being bombed in several major cities, China needs to make sure that shit will never fly in China's case. Meaning, if just one conventional missiles flies towards any Chinese city (being able to penetrate that is), the enemy bases on several islands will be double-tapped with tactical nuclear strikes. Simple as that. The same way the U.S. would not have tolerated that a Chinese missile hits an city in the U.S.
In order to have this as credible threat, China should push towards 5% defence spending or at least as close to that number as possible. Expanding brutally on conventional and - of course - nuclear forces, and making it very clear that also nuclear ones will be used, get rid of "No First Strike Policy".
That NATO target of 5% is due in 2035 and is composed of:
3.5% in direct military spending
1.5% in military-related spending
The US is already at this spending level, so it doesn't actually represent any extra spending.
It is many of the European countries which will have to increase military spending. But if you look at what they will likely be spending on, it is really relevant to Russia, but doesn't really affect China.
In any case, given the 2035 timeline and the speed/capacity of European military developments, China can likely offset anything Europe does. And do this faster and at lower cost.
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Also, consider what China doubling military spending to just 3% would mean. For example:
1. Total annual procurement of 5th Gen stealth fighters would likely be over 400 per year, but this will take at least 3 years to ramp up. Then with just 5 years of full-rate production, there would be over 3000 in the fleet.
2. Annual procurement of warships would also go from 2x to 4x the US rate. Roughly speaking, that would be the equivalent of China adding an entire US Navy in the space of 10 years. But again, it would take a few years for this to ramp. Plus mature SSN and aircraft carrier designs aren't quite available yet
I feel these numbers are too excessive, as I think the risk of an actual war is actually fairly low.