While China was celebrating the Lunar New Year, Pyongyang launched their third underground nuclear test a hundred kilometers away from their border with China on February 11, 2013.

So far the Chinese government's response has been moderate seeking dialogue rather than sanctions.

As usual, online opinion is divided into the “pro-North Korea” nationalist and “anti-North Korea” liberal camps. However, both camps are equally unhappy with the Chinese government's overall stance on North Korea.

Matthew Gospel AAA (@马太福音AAA) who belongs to the liberal camp believes [zh] the latest test is a slap in China's face:

【評論：中國是時候拋棄朝鮮了】勸阻朝鮮放棄核實驗，中國盡力了。本來有中國在安理會，聯合國制裁聲明徒有形式。中國數次避免過度刺激朝鮮，想把它拉回談判桌。但正月初三核爆，再次證明朝鮮毫不顧忌中國感受，不考慮中國利益。中國還忍著被當眾扇耳光羞辱，還勸說它嗎！不要姑息養奸了。

[Comment: China should abandon North Korea] China has tried its best to persuade North Korea to refrain from nuclear tests. The statement that Chinese government made at the UN Security Council carried no weight. Many times, China has tried to pull North Korea back to the negotiation table. The nuclear test on the third day of the Lunar New Year has proven once again that North Korea has no respect for China and does not take China's interest into consideration. This is like a slap in the face. Is there space for persuasion? Don't let the evil mind grow.

The Maoist website Utopia, which represents extreme nationalists, issued a public statement [zh] celebrating the successful launch of the North Korea nuclear test:

Location of the North Korea nuclear test. It is a lot closer to China than South Korea and Japan.

朝鲜顶住各种反动势力的压力，成功举行核试验，表明朝鲜劳动党和金正恩同志有能力、有魄力领导朝鲜军民走向社会主义强盛国家。朝鲜获得了中国人民的尊敬，获得了全世界有良知人士的尊敬。[…]

Against all the anti-revolutionary's pressure, North Korea has successfully launched its nuclear test. It reflects the ability of Kim Jung-eun and the ruling party in leading the North Korean people and its army for building a socialist strong nation. North Korea has earned respect from the Chinese people and people who have conscience all over the world. […]

旧事如画，历史如镜。五十多年前，坚强的中国人民在伟大领袖毛主席的领导下，成功爆炸了第一颗原子弹，成功打破了美国、苏联的核讹诈，保证了中国的国家安全，提升了中国的国际地位。那个时候，中国也处于和朝鲜今天类似的处境 […]

History is like a painting and mirror. 50 years ago, under the leadership of Mao Zedong, Chinese people had successfully launched its first atomic bomb test, shattering the U.S and USSR's nuclear monopoly, ensuring Chinese national security and improving China's international status. At that time, China was in a similar situation to what North Korea is presently in. […]

由于现行国际秩序袒护强权、践踏主权，朝鲜发展卫星、导弹和核武器，就是对人类和平正义事业的贡献。朝鲜掌握核武器，是正义力量对抵抗帝国主义的新贡献，将会大大遏制帝国主义和反动势力扼杀和包围朝鲜、中国的狼子野心。

The current global order is siding with strong powers who have no respect for sovereignty of others. North Korea's development in satellite, missile and nuclear technology contributes to human peace and justice. North Korea's nuclear weapons represent the power of justice counteracting imperialism, whose reactionary forces and ambitions are isolating North Korea and China.

Fortunately we can find more moderate and critical opinion. For example “Tomorrow will come” (@不会有到不了的明天) [zh] questions the location of the nuclear test:

有一件事实在想不明白。中国老大哥送米送油送钱送枪每天焦头烂额帮这小兄弟在国际社会擦屁股，朝鲜核试验还就选在中朝边境上，中国东北三省人民莫名陪绑。金三胖那么嘴强牙硬耀武扬威，一天到晚嚷嚷要灭了南朝鲜活捉李明博的，为毛不在三八线上搞核试？

I don't understand. Big brother China keeps giving rice and oil and money to his dirty little brothers and wipes their asses in front of the world. When North Korea picked its nuclear test spot, it chose the border area that threaten China's northeastern provinces. The fatty Kim Jung-eun keeps saying that he will destroy South Korea and capture Lee Myung-bak, why wasn't the nuclear test  at the border of North and South Korea?

Blogger Cheng Tan takes a step back and wonders [zh] why the ‘little brother’ disobeys the ‘big brother':

朝鲜深知中国不仅面临全球民主化浪潮的冲击，而且由于严重的官场腐败、贫富悬殊，累积了巨大的社会矛盾，根本不敢把朝鲜发展核武器对中国国家利益的巨大损害告诉民众，以免诱发民众借机发泄对社会现实的不满。

我个人理解，我们政府在朝鲜发展大规模杀伤性武器问题上真的是左右为难——基于“外交关系中国家利益高于一切”的原则，中国必须制止朝鲜发展核武器；但基于“党的利益高于一切”和国内社会“稳定压倒一切”的政治需要，又不能对朝鲜采取过硬的制裁措施。

North Korea knows that China is now under the challenge of the global democratization movement. Domestically, it has to handle social conflict generated by corruption and the disparity between the rich and poor. The Chinese government will not have open discussion about the threat of North Korea's nuclear development with Chinese people out of fear of arousing more social discontent.

The Chinese government is caught in a dilemma — according to the principle that “China's interests comes first in diplomacy”, the Chinese government should stop North Korea for developing nuclear weapons; yet for the “CCP, stability is the first principle”, so it cannot sanction North Korea.

Some extreme nationalists believe anything anti-North Korea is against the interest of China. For example, Zhang Hongliang [zh] (@zhanghongliang), a famous nationalist opinion leader, labelled those who opposed the North Korean nuclear test as anti-communism and anti-China [zh]:

【为什么反共反华的人全都反对朝鲜核试验】虽然反对朝鲜核试验的人并非全都反共反华，但是所有反共反华的人全都反对朝鲜核试验。相反，那些支持朝鲜核试验的人，全都是拥护共产党的爱国人士。美国强割中国南海、日本侵占中国东海，国内极右势力要共产党下台，中共与这些势力站在一起，将会是如何下场？

[Why  people who are anti-communism and anti-China are against North Korea nuclear test] Although not everyone who is against North Korea's nuclear tests are anti-communism and anti-China, everyone who is anti-communism and anti-China are against North Korea's nuclear tests. On the other hand, those who support the nuclear tests are supporters of the Chinese Communist Party (CCP) and patriots. The U.S. has cut the South Sea from China by force, Japan has invaded China's Eastern Sea, but the extreme rightists are advocating for the downfall of CCP. What would happen if the CCP works with such forces?

Zhang is not happy with the Chinese government's foreign policy [zh]:

在得知朝鲜核试验第一时间我们就指出，朝鲜是被美国逼上核武器道路的。如果中国不与美国站在一起，任凭美国背信弃义、一再欺骗朝鲜，如何会有今天？现在美国日本把中朝两国都作为敌人，朝鲜宣布核武器是为打击美国，中国却要把拥有核武器的朝鲜作为敌人，这不是自杀又是什么？

We pointed out soon after we heard about North Korea's nuclear test that North Korea has been compelled by the U.S. to arm themselves with nuclear weapons. If China had not sided with the U.S. in cheating North Korea, would such an incident have taken place? Now that the U.S. and Japan see China and North Korea as enemies, North Korea uses nuclear weapons to strike back at the U.S. China, on the other hand, sees North Korea as enemy, this is suicide.

Zhang's opinion has been echoed by other Maoists and nationalists, like Ran Xiang [zh], however many express their contempt. For example “I am a happy farmer” said (@快乐的我是农民) [zh]:

张宏良之流赞同朝鲜核试验，赞同的原因就是美日等国反对。这种人心里没有本国人民，没有社会正义，有的只是意识形态。这种人才是真正的卖国贼，是中国人的败类，我们应该为这种人感到耻辱。

Zhang Hongliang and his fellows support North Korea's nuclear tests because the U.S. and Japan are against it. They don't have the Chinese people and social justice in their hearts. All they have is ideology. They are the traitors and Chinese scumbags. Shame on them.

Zhao Shilin (@赵士林微博), an alumnus of the Minzu University of China urged [zh] the University to sack Zhang:

致中央民族大学全体师生：北朝核爆人神共愤，金氏邪恶政权的穷兵黩武遭到全世界同声谴责，但混迹于我校的文革孽种、政治投机小丑张宏良（成教学院副教授）竟冒天下之大不韪，公然鼓噪支持北朝核爆。这种反人类的邪恶行径令我校蒙羞，是我校奇耻大辱，呼吁开展＂驱张行动＂，令张滚出我校。转发即为支持

To all the teachers and students in Minzu University: All people on earth are angry at North Korea's nuclear test. Kim and his family's evil power and abusive military action has been condemned by the whole world. However, political opportunist and an offspring of the Cultural Revolution Zhang Hongliang, who is now working in our university has become an advocator of North Korea's nuclear tests. This is a shame to our university and I hereby make a public call to “Kick Zhang Out” of our university. Retweet this to show support.

This was retweeted more than 7000 within 6 hours of being posted on February 14, 2013.