While Pyongyang is dependent on Beijing for trade and diplomatic support, experts say the North Korean regime has always refused to play the role of little brother in much larger China.
Now that North Korean ruler Kim Jong Un is establishing himself on the world stage and preparing for summit meetings with South Korean President Moon Jae-in and US President Donald Trump, Beijing fears that Pyongyang will be out of orbit
Beijing's economic pressures have helped bring Kim to the negotiating table, fearing Beijing that Kim may now agree to an agreement that brings his country closer to its old enemies and further away from its traditional ally, hunger and global isolation.
"There is even extreme concern within the strategic Chinese community that the US may accept a nuclear North Korea as its ally, or at least a friendly country," said Tong Zhao, a nuclear policy expert at the Tsinghua Carnegie Center for the United States global politics in Beijing.
These concerns have been exacerbated by the tense relations between China and the US when the Trump government debated the encouraging Chinese President Xi Jinping.
"Some of the concerns are so extreme that it almost sounds like a conspiracy theory, but it reflects that deep, deep-rooted Chinese suspicion about the US and North Korea," he said.
For more than half a century, the status quo worked well for China ̵
But Pyongyang's quest for its own nuclear weapons, which intensified under Kim Jong Un, changed that balance – and raised the specter of a regional arms race in front of China's doorstep, the risk of US preemptive military action and its allies, or an unintentional outbreak of conflict.
Beijing could not tolerate that.  "China has always wanted to maintain a normal and stable relationship with North Korea, and China has no disagreements with North Korea in any problem area other than nuclear power," Zhao said.
"China had to react strongly to North Korea's acceleration of nuclear development – China had to join the rest of the international community to impose sanctions."
Kim also cleaned several key officials who had close ties to Beijing, including his uncle Jang Song Thaek, who angered his main patron.
Relations suffered and the two traditional allies barely landed.
Kim's quick approaches earlier this year, which suggested talks with South Korea and with the US, though not unwelcome, caught Beijing unprepared.
The look was unequivocal: Kim paid homage to China by traveling to the capital to inform his great neighbor and ally and seek his advice and blessings. President Xi made a show celebrating Kim, reminding the world that China is on North Korea's side and remains a key diplomatic player on the Korean peninsula.
"China does not like the current image of the two Koreas and the US Central Theater without China, and Beijing's main concern is the chance that it will not be able to exert its influence and interests in the region," said Duyeon Kim, Senior Fellow at Future Forum of the Korean Peninsula in Seoul.
Will the maximum pressure stop?
Beijing fears both economic and political collapse, fleeing refugees across the border and leading to a possible reunification of the North with the US-allied South.
Shortly after this announcement, a comment in the shrill, state-run Global Times explicitly stated this viewpoint: "If Washington still forces Pyongyang to renounce its maximum pressure on nuclear weapons, it will become dangerous. Neither China nor South Korea will It will probably usher in a return to even greater turbulence. "
" The international community should encourage North Korea by imposing some sanctions and resuming certain exchanges. "North Korea will show the tremendous benefits of its return to the international community. and the importance of its nuclear weapons will increase its security. " 19659002] There is evidence that this opinion is shared by the Chinese government.
"We believe that all resolutions should be implemented in their entirety and that the sanctions and resolutions of the DPRK include not only sanctions, but also measures to promote denuclearization and promote peace and stability on the peninsula," he said Foreign Ministry spokesman Lu Kang week.
Ultimately, Xi does not want the US to rule in a region where China is increasingly in charge, in a region where relations between Beijing and Washington are at a low point.
Kim, the analyst, says Beijing will seize every opportunity to undermine US credibility and influence the outcome of the two summits.
"If Beijing is not happy with the outcome of the two summits, it could dismantle America's efforts to democratize North Korea by lifting sanctions against the North, creating a safe haven for its illegal activities and refusing to implement existing ones "Easily destroy future UN sanctions," she says.