Four different ways for China to attain MAD capability against the U.S.
It is important to make a distinction between China's Mutually Assured Destruction (MAD) capability against the United States and the actual implementation. The point behind acquiring MAD is to deter the United States and prevent the use of the Doomsday weapons.
China's MAD capability is not about destroying the United States via the destruction of Russian cities to trigger the Russian thermonuclear arsenal. The strategic goal of China's MAD is to force the United States to go home.
The Soviet Union/Russia successfully used its thermonuclear arsenal to force the United States to remove its thermonuclear weapons from Turkey during the Cuban Missile Crisis in 1962. Russia again successfully used its thermonuclear arsenal to deter the United States when Russia invaded and annexed 20% of Georgian territory in 2008.
The idea behind the Chinese threat to use 288 thermonuclear warheads (carried by 36 JL-2 SLBMs on three Type 094 Jin-class SSBNs) to wipe out Russian cities is to piggyback on the Russian thermonuclear arsenal. Since China's response to the U.S. threat of Trident II SLBMs is the same as the Russian response in Georgia, China will be able to "stare down" the United States in Asia.
China's leverage of the Russian thermonuclear arsenal is an indirect MAD. The entire scenario of wiping out all Russian cities and towns is to put the Russians into a box with only one rational choice of counterstriking the Unite States.
However, there are three other ways for China to achieve MAD capability against the United States.
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Firstly, as J-20BlackDragon has mentioned, China has the 3,000-mile Underground Great Wall. The problem with the Underground Great Wall is that no one knows how many thermonuclear weapons are down there. Is it hundreds or thousands of thermonuclear warheads on DF-31As? The distinction is crucial. The DF-31A is either 3-MIRVed (according to Jane's Defence) or 6-MIRVed (according to Bill Gertz).
The low MIRV count on the DF-31A is a problem. With 100 DF-31A ICBMs, China only has 300 to 600 thermonuclear warheads. As a military strategist, we like to be conservative and pick the lower number. You cannot deter the United States with 300 thermonuclear warheads.
The Pentagon's latest report on Chinese Military Power acknowledges the existence of "enhanced" DF-5 ICBMs. Since 1999, Richard Fisher has been discussing the DF-5B/"enhanced" 10-MIRV ICBM. China probably has about 20-35 DF-5B ICBMs. Using the lower figure, we are looking at another 200 thermonuclear warheads.
In total, a reasonable estimate is about 500 thermonuclear warheads in the Underground Great Wall. It is possible that China built a lot more DF-31A and DF-5B ICBMs. However, there is no proof. Also, China knew the more capable DF-41 was waiting in the wings. It is logical for China to build a limited number of DF-31A ICBMs and the liquid-fueled DF-5Bs.
Without more information, the Underground Great Wall is not currently sufficient to deter the United States.
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Secondly, China can deter the United States with a sufficient number of DF-41 10-MIRVed ICBMs on mobile TELs. It has been 1 1/2 years since the first known successful DF-41 test on July 24, 2012. Assuming China builds 20 DF-41 ICBMs per year (which will probably ramp up to 40 DF-41 ICBMs per year after three to five years due to greater experience), we can conservatively estimate China to have about 30 DF-41 ICBMs. That's 300 thermonuclear warheads.
Once again, 300 thermonuclear warheads will not give China MAD capability and it is insufficient to deter the United States.
Collectively, we are looking at 800 Chinese thermonuclear warheads. There might be more due to reload capability (of a second missile) per mobile TEL. However, the United States clearly has the upper hand.
China can achieve direct MAD capability against the U.S. in about 3.5 years with its mobile DF-41 TELs. When we see pictures of DF-41s being deployed to every Second Artillery battalion then China has achieved MAD against the U.S.
On July 24 2017, it will have been five years since the first DF-41 launch. Assuming an average production of 30 DF-41 ICBMs per year, that's 150 DF-41 ICBMs in total with 1,500 thermonuclear warheads. We're definitely entering MAD territory.
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Thirdly, China can achieve MAD with a reasonable number of JL-3 SLBMs. The current JL-2 SLBM doesn't have enough range to threaten the continental United States. The improved JL-2A SLBM with longer range might be able to hit part of the continental United States, but the number of MIRVed warheads will probably go down to allow the JL-2A SLBM to carry more fuel.
As a new missile variant, the JL-2A SLBM will be produced in limited quantities and the reduced MIRV warhead count weakens its total impact.
Thus, we have to wait until the JL-3 SLBMs (which are navalized DF-41 10-MIRVed ICBMs) make its debut. Afterwards, we will have to wait a few years until the JL-3 SLBMs are produced in sufficient quantity to deter the United States.
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In conclusion, it should be apparent that China is on the brink of achieving direct MAD capability against the United States. Within the next five to ten years, China will be able to field sufficient thermonuclear warheads against the United States to force an U.S. retreat from Asia.
That is why the U.S. is pressuring China now to agree to a code of conduct and attempt to bind China into a legal agreement on the South China Sea. The U.S. won't have this leverage in five to ten years.
The interesting aspect of China's ability to deter the United States via the Russian thermonuclear arsenal is that it deprives the U.S. of any leverage over China today. Since China can destroy the United States by first destroying Russian cities, China should not give in to American pressure on the South China Sea.
