Why do South Koreans protest against the US and Japan, but not China and North Korea?

This is a good question, asked recently at One Free Korea and echoed at ROK Drop, in the wake of China sending back nine North Korea defectors to the DPRK, where their fate is almost certainly imprisonment, torture, and even death.

I will polish the following up sometime later, but for now the following is the response I left at ROK Drop.

Anger toward China has been growing as Beijing becomes more brazen against South Korea, to the point where South Koreans no longer feel they have to go along to get along with China because even going along isn't working; China is clearly intent on making South Korea its whipping boy and a proxy for anger against the state. Consequently, there are more and more protests against China, commensurate with the brazenness of the acts and the perception that China is a bad actor.

That said, if the tendency of protesting against the US and Japan but not against China and North Korea holds true, it's for several reasons.

First, it is the North-sympathizing chinboista fringe that is behind many of the protests, which leads to regular protests about anything against the US, as well as a coordinated boots-on-the-ground effort in the case of something big (like killing nine South Koreans) regarding the US, South Korea, the ROK government, or a major corporation (they are also anti-corporate and anti-ROK government, in addition to anti-US and anti-Japan).

Second, for mainstream Koreans, there is a perception that the United States and, to a lesser degree, Japan are "supposed to be on our side" and thus held to a different (usually higher) standard. South Koreans will protest against Japanese textbooks watering down the occupation but not against Chinese textbooks that claim South Korea invaded the North on June 25, 1950.

Finally, there had been a perception, related to the second one, that protesting against China or North Korea was futile. Not so with the US and Japan, since they are ostensibly both allies and the ROK government can be persuaded vis-à-vis its relationship with Washington and Tokyo.

This last point is largely changing, however, as the aforementioned anger toward China grows.

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