Because they'd have ground based radar systems as well, and US wouldn't have any SAM sites in China

The F-35 is the only fifth gen US fighter capable of carrier use, and it hasn't entered mass production yet.  The SU-30MKK is a modern fighter, and is considered a 4.5 generation fighter, most SU-27's that China flies are modern and quite capable fighters.  US would be fielding F/A-18's which according to DERA is less capable than an SU-27M (AKA SU-35), according to DERA the F/A-18 only has .4 to 1 odds of beating a SU-27M/SU-35, so its very unlikely that the US's F/A-18's would be able to achieve air supremecy, in fact its very likely we'd have a lot of dead US pilots

The only country's I think would be able to stand up against are China and Russia.  The only real outcome would be nuclear war.  But im sure both russia and china would join forces.  And the europeans would just stand by and watch as europe is dam to weak these days.

Russia may look like a ageing army but if it came to war the Russians would throw everything at the USA, the all nation would defend the mother land like it was back in 1941-45.

China would never allow itself to be taken over by any western powers and it too would fight to the bitter end.  And no way would the USA ever gain air superiority over china,  Just think how big China is and how many people china has, over 1 billion at the last count.  But like I said in another post is... china will one day overtake the USA military, its just a matter of time.

Another point is I don't think the american people want total war with nations like china, russia because....

1. To many american's will died for nothing.

2. It will drain the america economy of money and the american people don't want to suffer.

3. The amrican's will need to conscripe tens of millions of men to go fight, mostly would be from poorer backgrounds.  While the poor fight and died the rich stay at home.

China will most probably overtake the US's economy in the future but it will still be sometime after that before its military surpasses the US's. But yes it will happen eventually barring a significant change in the way the world is going currently.

I just read a couple of papers submitted to Congress, and research documents.  The conclusion is that in all liklihood the United States would successfully be able to subdue China on it's own turf.  But there would indeed be massive casualties for the US due too China's air force, anti-ship missles and SAM sites.  Ultimately the US hopes to counter this with Prompt Global Strike (PGS) and F-22 Raptors.  They would allow the destruction of the Chinese military access denial assets far more effectively than exposing the Navy too said anti-ship cruise missiles and air defenses.

Ooops sandbox section of the forum... my bad... bye...

Lets compare some ORBATs when talking about US-Chinese air superiority (since I see Avinash spouting things that are technically true, but very misleading):

The Chinese do have modern fighters, but very few. The vast majority of their airforce is very archaic.

From Wikipedia, it shows that they have:

Fighter/Interceptors:
125 J-11's (SU-27 clones. Most are early SU-27s without the advanced avionics suite the 11B has)
120-160 J-10's (F-16 clones)
400 J-8's (SU-15 clone. See J-7)
500 J-7's (Mig 21 clones....Useless other than human wave tactics. Unless they were fighting in Korea, Taiwan or Japan, they would be fodder. Our PHALANX systems would have a field day with these things)
100 SU30MMK's (Top-O-The-Line Russian fighter/bombers. Very good aircraft)
76 SU27 Flankers (Very good as well)

Bombers:
100 JH-7's (F-111/SU24 clones. Decent, but nowhere near top of the line)
120 H-6's (TU16 clones. Very good heavy bombers)
480 Q5's (Mig 19 clones...Useless ground attack aircraft)

Now, when you argue about America's capability to attack China, you have to remember: We wouldn't just use naval aircraft. We have multiple bases in the theater in Japan, Korea and Guam. This would allow an influx of aircraft that aren't usable on a carrier such as the F-22, B52, B1, and others.

The airbase at Kadena, Japan, would be especially difficult to deal with by the Chinese, since it lies only a few hundred miles from the Chinese coast...Certainly close enough to launch any aircraft to attack the shores of China.

And the US has:

67 B-1 Lancers
21 B-2 Spirit Stealth Bombers
85 B-52 Stratofortresses
196 A-10 Thunderbolts
500 F-15 Eagles
700 F-16 Falcons
97 F-22 Raptor Stealth Fighters
25 C-130 Spooky/Spectres

Then add in the roughly 500 F-18's in service with the Navy, and you'll see why the US air force would decimate the Chinese airforce. China has roughly 400-500 decent fighters with the J10/11 and the SU 27's and 30's. The US has roughly 3 times that number in modern aircraft.

The US would achieve air superiority quickly. The only real question is how skilled are Chinese pilots (which I think favors the US heavily), and how good their air defense is, which is a major cause of concern. IMO, the major issue if the US ever had to fight on Chinese soil would be their air defense capabilities...Which would be viscous. Ultimately, the US would win, but we'd have a lot of great aircraft shot down due to ADA, not Chinese airforce.

And the F-15E/K/SG, F/A-18E/F Super Hornet and the F-16 Block 50/52 are also considered to be 4.5 generation aircraft as well.  Not to mention that the Chinese military only has about 100 of the planes you speak of with the majority of their other planes being lesser 4th gen fighters. As for your SU-35 their are only 12 in exsistence, and all are controlled by the Russian Air Force.  And you keep mentioning DERA like its concrete information, it was a war simulation.   The pilots of every plane were all considered equals, but anyone who knows anything about military powers knows that the US Air Force pilots are second to none.

Chinese airforce is rotten. Their two thousand rusting Mig 21s would be no match even for the Swedish military airforce (a lil over 100 Saab JAS Gripen fighters).

An American carrier full of US fighters would easily crush the whole Chinese airforce.

Those Saab JAS-39 Gripen planes are also 4.5 gen fighters, and are arguably one of the best planes in the world. 

One of the things to take into consideration when comparing PLAF to USAF planes and abilities:

The reason that some are so negative on PLAF abilities lies in how few 4th gen fighters they have, and the specs of the bulk of their airforces with their J7 and J8 aircraft.

For the J7, they are only able to carry short range missle suites, namely with the PL8's and AIM9L systems. They have a maximum effective range of upto 20km. Good, but that's barely above BVR

For the J8, they can carry the more advanced PL9 medium range missiles, which have a maximum range of 75km. This means J8's can engage in BVR engagements. Very important to note this (their radar also supports upto 70km range). You must remember this, because it means that they aren't going to be able to track and fire at an aircraft at that range, which means they'll have to be forced into a closer fighter, in order to track and shoot another plane.

Also you must note the hardpoint availability on the J7s and J8s. Since they use very old designs (circa 1960), they cannot support large hardpoint arrays. The J8's may carry a maximum of 4 missiles at any given time.

For US fighters, all are equipped with AN/APG radar suites that allow for tracking and engagement upto 300km, and AAMRAMs are capable of engaging targets upto 105km.

Essentially, in an engagement, the J7's would be destroyed before they could even get close enough to engage any sort of American aircraft, unless they bounced a group of less-armed bombers, which is almost an impossibility. The J8's would be slightly tougher, but due to the fact that they can't track another fighter until it's within engagement range, it would likely mean that an American fighter could get a few shots off before the J8 is within engagement range as well.

Therefore, both J7's and J8's would be destroyed before even getting a shot off. The J10s, 11's, SU27s and 30s would be near equal to the American fighters, therefore it would come down to skill which....Given the specs...The Americans would win.