You've made some serious assumptions all of which, in my opinion, are wrong.
The first assumption you've made is that the US has the support necessary to engage China in the Pacific.
With regards to NATO you need to review Article 5 of it's charter which states:
"The Parties agree that an armed attack against one or more of them in Europe or North America shall be considered an attack against them all and consequently they agree that, if such an armed attack occurs, each of them, in exercise of the right of individual or collective self-defence recognised by Article 51 of the Charter of the United Nations, will assist the Party or Parties so attacked by taking forthwith, individually and in concert with the other Parties, such action as it deems necessary, including the use of armed force, to restore and maintain the security of the North Atlantic area."
Article 5 ONLY relates to attacks on the NATO members states mainland not actions in the Pacific Ocean nor does it include defense of US "allies" who are non-NATO members like Japan, India or Australia.
China is the worlds largest consumer market, it's already Australia's largest trading partner and soon to be Japan's if it isn't already not to mention its part of a huge chunk of the worlds supply chain so what nations would seek to commit economic suicide for the US war of terror on the high seas?
Furthermore many of the nations that the US has naval bases in like Saudi Arabia, who export 70% more oil to the Chinese than the US, wouldn't allow their ports and naval bases in their country to be used to attack the PLAN if only out of purely economic reasons so it makes a lot of the US' bases/ports of call completely worthless in a fight against China.
If the US engages China in the Pacific it's on its own particularly in light of the fact that among the populations of many of Europe's biggest NATO members (ex. Germany, France and Turkey) support for the organization has declined considerably over the years and I don't see how any of their respective governments would even be able to garner the necessary public support to fight China in the Pacific when they won't even take on Russia in Ukraine.
The second assumption you've made is that the US has the capacity and capability necessary to engage China in the Pacific.
The head of PACOM, Adm. Philip Davidson, himself confirmed to the Senate Arms Committee when he was still a nominee that China has almost complete control over the South China Sea with capabilities they've developed/installed over the years:
https://freebeacon.com/national-sec...military-islands-now-control-south-china-sea/
It's only set to get worse.
Not only does China have the worlds largest, and likely fastest growing, Navy on the planet as confirmed by the Pentagon but the ships that the US does have are pre-occupied with a host of missions globally so they could never allocate all their assets for such a fight in the Pacific to begin with.
https://news.usni.org/2020/09/01/pe...st-navy-as-beijing-expands-military-influence
It's clear that many nations and groups will directly or indirectly attack the US and its "allies", many of whom are despotic regimes, globally once this war kicks off and the US is preoccupied by it.
So will the US Navy will just abandon despotic Gulf regimes?
So will the USN abandon its position in Europe or leave the US mainland vulnerable to attack and what about their missions in South America and Africa?
As for China isn't alone either and has ports they can call on aside from their large expanding naval base in Djibouti. While a sizeable chunk of the US military budget is required simply to maintain military/naval bases globally it doesn't go into the production and acquisition of actual war fighting material which isn't something China is required to do considering the Pacific is their own backyard while the Chinese are also expanding their naval footprint which is is largely coupled with economic projects making them far more sustainable than the US presence globally.
As for spending If China matches what the US spends as a % of GDP based on their nominal 2018 figures alone they'd have another ~$163 Billion a year they could put towards their armed forces specifically the navy so just imagine that over the next 5-10 years.
That increase itself would be almost triple the current Indian defense budget.
You also fail to realize is that the Chinese GDP (PPP) is over 25% higher than the US' and since they can produce advanced military technology on their own, whereas nations like India are required to import a significant portion of it, their money goes a lot farther.
Add the fact that China's position as a global manufacturing hub has given them a massive infrastructure advantage over the US which can be utilized towards the production of weapons systems on scale the larger US military budget doesn't have the same kind of impact you might have thought it did.
This is typical Indian nonsense.
They continually talk about "conventional superiority" in relation to Pakistan but suddenly "conventional superiority" doesn't mean anything when it comes to a fight against China.
They themselves are in a mad dash to procure light tanks, especially considering they have nowhere near the infrastructure developed in the territory they illegally occupy that China has in the liberated regions, but suddenly those light tanks don't give China an advantage:
https://eurasiantimes.com/indian-vs...-answer-to-chinese-type-15-lightweight-tanks/
https://swarajyamag.com/defence/ind...tandoff-with-china-heres-what-you-should-know
I personally don't think buying drones is going to bankrupt the Indian Armed Forces, though they won't be able to match the numbers the PLA can put forward considering they'll need drones with extensive protection against EW attacks which they don't have, but China's increased troop presence along the entirety of the LAC itself will push India towards spending A LOT more of its defense budget arming, feeding and housing soldiers versus acquiring actual war fighting capabilities.
This is why India is so desperate to stop China from pushing more troops along the LAC:
https://timesofindia.indiatimes.com...nt-in-military-talks/articleshow/78263195.cms
