Okay, so the main thing is - can China allow a united Korea with a popularly elected government? They are second only to the North Korean government as an obstacle to such a unification. Any election favors the South because they have a lot more people than the North. Are there any conditions under which China would allow this to ever happen??

Why not?

The united Korea has been on the Chinese border for thousands years, no big deal.

Actually S.Korea has a very good relationship with China this moment, and more and more Koreans are learning Chinese (their forefathers all used Chinese writting system for thousands years), and China is getting stronger and stronger, why not for but against the united Korea?

The only issue is: US troops must be out of Korea, then it is quite OK for China to see the united Korea.

North Korea and China are not really that close of an ally anymore. When China entered the Korean war on the North Korean's side, one must understand the situation that China was in. China became a true communist nation in 1949. The Korean war followed directly afterwards. With Mao in control the Chinese were basically obliged to help the North Koreans. Nowadays China started the 6 nation talks etc. I don't see why CHina wouldn't want Korrea to be united. As FF said, South Koreans are now required to lelarn Chinese in their schools, this just shows their good relations.

Relations between China and North Korea... well there are some key differences. There are several thousand (apparently some estimates go up to hundreds of thousands) of North Koreans living illegally in China. It seems China is reluctant to force them to go back... after all they know what will await a good deal of them.
I know that there was a unified Korea near China for a long time but times have changed. South Korea is an ally of the United States and is an (at least for all practical reasons) ally of Japan. China cannot afford to have a country like that border itself. The only way China will let a unified Korea to be on its border is if the South decides it wants to side with China.
That itself won't be an easy thing to do.

Frog, is what the_13th_redneck essentially true?? Would it be a condition that they drop all alliances with the United States and Japan before China would allow it? The withdrawal of US troops is somewhat obvious as a condition, but at the same time ... the US force in SK is tiny and not large enough to be any threat to China at all. So is it just the principal of the thing? To what degree does a united Korea exist only until they become an inconvenience to China? How much influence would they have to accept from the PRC for the priveledge of sharing a border?

Answering the question about US Forces in Korea:
The US ground forces in Korea are pretty much a token presence and their numbers will continue to shrink for some time. Also they are getting further and further from the front line. It's a delayed realization on all sides that South Korea's military's good enough to handle things on their own.

There are will be a chain reaction:

A unite Korea won't allow US to put troops there anymore.

Soon, Japan will request US withdraw the troops.

And war-race will start among China, Korea and Japan

When fully armed Japan reborn, its first target it return the nukes back to US.

..........

So, I donot see US have a reason to allow Korea to reunite.

The current situation is best for all.

I think the first three steps are rather reasonable but I think the last one is just pure fantasy.
1) A united Korea won't allow US to put troops there anymore.
My view: It really depends on how relations are with China... and eventually Japan. A united Korea may decide to hold the "neutral" card in the struggle between the two. Both China and Japan will want to wield as much influence over Korea as possible because in case of conflict, the addition of Korea could give either side the edge. Korea will want to have a strong enough military to guarantee its neutrality in this region. This may require the complete withdrawl of American forces. But it will include the neccessity of Nuke ownership.

2) Soon, Japan will request US withdraw the troops.
My view: Once Japan's allowed to have its own full fledged military, I don't see why this request won't be made. Unless of course, Japan realizes that China is a big enough threat to warrant American alliance. Then the US will probably stay in Japan.

3) And war-race will start among China, Korea and Japan
My view: It's already pretty much begun. Japan's got the foundations of a brilliant military, China's doing a fine job of modernizing its massive army and South Korea is constantly improving its military. Korea will also know it has a tradition of winning wars one way or another throughout the years. It only lost completely in war (i.e. taken over by conquerers) twice. Once by the Mongols and once by the Japanese. They will look to continue this tradition.

4) When fully armed Japan reborn, its first target it return the nukes back to US.
My View: That's just stupid.

Originally Posted by whosewar2000

There are will be a chain reaction:

A unite Korea won't allow US to put troops there anymore.

Soon, Japan will request US withdraw the troops.

And war-race will start among China, Korea and Japan

When fully armed Japan reborn, its first target it return the nukes back to US.

..........

So, I donot see US have a reason to allow Korea to reunite.

The current situation is best for all.

Originally Posted by the_13th_redneck

4) When fully armed Japan reborn, its first target it return the nukes back to US.
My View: That's just stupid.

While, US never allow Japan to develope its own nuclear program at all, no, NEVER, even ban Japan to even think about it. That is US always want to "protect" Japan, so they can refuse Japan's any excuse by: "We have enough nukes, what do you need for?"

Man, you guys nuke them twice....

Even if somehow Japan turned manical and wanted revenge against the US, their nukes would be countered by MAD.

Barely a theory worth shooting down.