That China strictly implements the UN Security Council resolutions that sanction North Korea is seen by all. If Pyongyang continues with its nuclear and missile tests, China is bound to support more harsh resolutions on this country.The relationship between China and North Korea has already been severely affected. Since Kim Jong-un became the leader of North Korea, there have been no leadership meetings between the two sides. Although they maintain smooth diplomatic communication, strategic mutual trust between the two is scarce.As the situation in the Korean Peninsula worsens, Beijing-Pyongyang ties may further deteriorate. China should ready itself for unfriendly activities by North Korea.The past friendship between the two was the result of Northeast Asian geopolitics in the last century. It also fitted the national interests of the two countries at that time. The current bilateral relationship should be a normal country-to-country one first, and they can form a close friendship based on that. But the precondition is that China's national interests shall not be violated and Beijing shall not pay the price for Pyongyang's extreme policies.The issue around the peninsula generally is the conflict between the US and North Korea. But Pyongyang carries out nuclear tests only 100 kilometers from the Chinese border, and this threatens the security of Northeast China.North Korea's development of nuclear and missile technologies also intensified the situation in Northeast Asia, giving Washington an excuse to enhance its military deployment in the region. This means China cannot be a bystander.China should be firm in opposing North Korea's nuclear programs. Although Beijing and Washington have different strategic calculations, they share common interests in opposing Pyongyang developing nuclear and missile technologies. Beijing imposes pressure on Pyongyang to safeguard its own national interests rather than working for Washington.Some Chinese people worry this would render China with no cards to play in the face of the US and South Korea and it could lose its strategic buffer in Northeast Asia. At least for now, what North Korea is doing goes against China's strategic interests.From a long-term perspective, China takes the initiative of Sino-North Korean ties. As long as North Korea abandons its nuclear programs, bilateral ties can easily go back to normal.If the North Korean nuclear issue boils over, a war on the peninsula is unavoidable. The war will bring more risks than the tough sanctions on Pyongyang could to China. If China does not tackle the conundrum now, it will face more difficult choices in the future.The nature of China's sanctions is different from that of the military threat from the US and South Korea. As long as North Korea holds the slightest rationality, it will not end up militarily confronting China.As long as China breaks Pyongyang's illusion that it can ease Beijing's sanctions through diplomatic means, China will establish its authority toward North Korea.China aims to suspend both North Korea's nuclear tests and military exercises by the US and South Korea. China should make clear to the US and South Korea that China is not key to solving the North Korean nuclear issue. Nor will China articulate its North Korea policy based on their interests.Beijing hopes to maximize the interests of all stakeholders. But if it fails in the end, it still has the capability to strike back at any side that crosses the red line.