USA cannot defeat Chinese military totally. Well they can cripple Chinese navy and some of the frontal ports. But that will come at huge cost for USN. US will use all of its allies Japanese and other ports but Chinese will target them with rocket force and will cause huge damge for the Americans there air superiority will be challenged by Sam system grid around the Chinese costal area.
For Americans logistics will remain a huge challenge and for Chinese mass manufacturing of missiles in today's era tanks and bs doesn't make sense if Chinese want to suppress American aggression from Japanese and American bases they will need to bomb them with thousands of missiles daily.
Eventually Americans will gain air superiority but but they will get totally slaughtered if they try to step inside Chinese land with military boots.
And let's don't talk about nuclear missiles and all. Technically saying both Chinese and USA have enough nuclear arsenal to wipe each other.
Well, no. The USA can wipe China's yellow face on the floor.
Sometimes between the lines of shiny-looking Chinese toys and HD propaganda videos, we misjudge China's might.
Let me explain.
If you control the lands around a landlocked country (Nepal), you can defeat it by choking its supplies.
If you control the seas, you can tumble even mighty economies.
If you control the airspace, you have the supreme power to defeat any country.
What is the strongest-side of the USA? It is its NATO allies and supreme veto powers.
What is the strongest-side of the USA militarily? It is its air force.
China has a mighty navy, no doubt. But you don't fight ship vs. ship exactly, if that happens, the USA may take massive losses. You send in jets to deal with the same.
In WW2, Japan had one of the most formidable Navies, as well as massive shipbuilding and industrial capacity, which made massive Yamato-class destroyers nearly double in size and tonnage of any ship the USA had. In event of any attack, it can fend-off multiple ships with its massive 46-cm main guns.
Result? All of them were sunk by attacking US navy planes.
So yeah, USA will not go marching with boots on the ground on the Chinese mainland.
An Chinese defeat will take place in these consecutive steps -
Step 1) Naval blockade, airspace denial - Chinese ships will be picked up using standoff-weapons and CMs. Blockage of the Malacca-strait, as well as the Pacific, starving China of crucial supplies like hydrocarbons and raw materials. Industrial productivity will go down.
Step 2) Massive air campaign to take out the Chinese air force and SEAD operations - Chinese air force is the weakest of all three. 3 US CBG in the South China sea, 2 off-shore Japan, and 1 in Bay of Bengal. Air operations will be supported by friendly countries like India, Japan, Taiwan, South Korea, the Philippines, and Saudi Arabia.
Step 3) Air raids on the industrial sector, runaways and harbours - Essentially crippling the country from producing more weaponry. At this stage, any country is pretty-much defeated.
Step 4) Gradual chipping away of territory, balkanization - China, now economically as well as militarily weak will be vulnerable to militancy and rebellion. Occupied areas like Tibet, Xinjiang will be first to be separated. Furthur degradation will happen as China with its massive population falls into a massive economic crisis and inflation.
Question - Yeah, it all sounds good, but what if it turns nuclear? Will China not use nuclear bombs?
Answer - All countries who possess weapons of mass destruction (including Pakistan) understands that it is more like a mutual suicide button. So its threshold of use is very high (like attacking and occupying a large area of the country).
The trick is to never let the country feel such external crisis and threat to the civilian population. If the country thinks it can live for another day and try again, they will choose to do so rather than forfeiting any chance of survival.
So, boots-on-the-ground on the Chinese mainland is a complete no-no.