I anticipate that there will be a number of initial negative shocks for China in a PH-China proxy war.
1) First, there will be the mother of all economic sanctions. The US will look at any proxy war with China as the greatest opportunity to kneecap China's economy. We should expect all kinds of sanctions. The Republican chicken hawks have already telegraphed to everyone their intention to nullify the debt owed to China. The US will attempt to seize Chinese USDs and assets in their banks. Kicking China out of SWIFT is definitely on the cards. All of this is not without grave consequences for the Americans, but they are not being led by smart people these days.
China will have to ride out the initial economic shocks. It'll be painful, it'll upset alot of Chinese, but this is when Chinese patriotism will shine through. This is the period where all those hanjians will start to show their faces. This will be a great opportunity to weed out the traitors. This is also an excellent opportunity to restructure the economy to make it much more war-resistant against the West. I believe that the CPC would have already learned much from the Ukraine War.
2) Second, there will be another great information war. I anticipate that the PLAN might suffer some minor setbacks during the initial phases. China had not been in war for decades already, so there will be some rustiness. Maybe a plane gets shot down, or a ship get hit. The anti-China media will be spare no effort to humiliate the PLAN and hype up the "brave Filipinos".
China will have to manage the image of the PLA, especially among the Chinese citizens. Just like in Russia, there should be severe punishments for Chinese citizens who insult the PLA in a time of war. Losses are inevitable, and all war is hell, even a righteous one. The PLA needs to focus on its job of defeating the enemy, and the last thing it needs are political distractions. Eventually the mistakes will lessen, and the fight will go even more their way.
3) The West will organize a general boycott and shaming of China. China shall be cancelled everywhere. In sports, in media, and in trade. We should expect bans for Chinese athletes in the Olympics and other Western-led sporting events. Some big brands might cancel commercial deals with China just like they did with Russia, so good riddance to them. China might get disinvited by several Western-organized forums. Anti-China countries might suspend entry for Chinese visas. Chinese-owned overseas assets might get confiscated by hostile governments. The West along with their lackeys will surely attempt to pass multiple UN condemnations of China. Basically it's gonna be another round of turbocharged Sinophobia racism, but worse than the one during the Covid years.
I believe that the Trump administration and Covid will have already toughened the Chinese to any further Sinophobia. Nothing much is gonna shock them anymore. So this negative setback should be the easiest to overcome. Some sporting and commercial events will be missed, but the nation always comes first.
4) This is speculative, but maybe the West will also attempt to organize a shadow blockade of China. They are likely to give the PH the weapons and the intelligence to strike at any Chinese civilian shipping that they can reach. They'll declare Chinese civilian vessels as "fair game", because they make and bend the rules. Western shipping firms will declare the SCS a conflict zone and therefore decline to provide shipping insurance. The anti-China countries might attempt to decouple as best they can, some might even go all the way to complete decoupling. That's gonna be their loss anyway.
This would be the time for China to activate its alternative trade routes built under the BRI program. China's trade network will have to be adjusted to reflect the new reality. It'll still hurt China's economy, but China can recover and still prosper once the adjustments are completed. China is the largest trading nation on earth, so anybody attempting to curtail is trade is gonna end up hurting the global economy, i.e.: themselves included.
