The UN Security Council voted yesterday to impose a fourth round of sanctions on North Korea, following the country’s February 12 nuclear test. The resolution was the outcome of three weeks of diplomatic haggling, in which the US pressed China to agree to more severe economic penalties against North Korea, Beijing’s ally.

Susan Rice, the US ambassador to the UN, boasted that “the strength, breadth and severity of these sanctions will raise the cost to North Korea of its illicit nuclear program.” She declared that the measures would “bite and bite hard” and “increase North Korea’s isolation.”

The US, which has maintained an economic blockade of North Korea since the end of the Korean War in 1953, has already ensured that it is one of the most diplomatically and economically isolated countries in the world.

The most potentially damaging new sanctions are aimed at choking off North Korea’s banking and financial system by freezing international transactions, including bulk cash transfers, based on the claim that they might be connected with its missile and nuclear programs. The resolution also bans government support for trade deals with North Korea that could allegedly involve such programs.

For propaganda purposes, Ambassador Rice highlighted the bans on luxury items, including jewellery, yachts and expensive cars, declaring: “North Korea’s ruling elite, who have been living large while impoverishing their people, will pay a direct price for this nuclear test.” In fact, the chief responsibility for the impoverishment of the North Korean people lies with the US-led embargo imposed on the country for the past 60 years.

The resolution mandates UN member states to expel anyone believed to be working for blacklisted North Korean entities. It requires aircraft or vessels coming from, or headed to, North Korea to be inspected for suspect cargo, and for access to airspace and ports to be denied to those ships and planes that refuse.

Pyongyang responded to these punitive sanctions with its own threats. Hours before the resolution was passed, the North Korean foreign ministry issued a statement declaring that “the US is set to light a fuse for a nuclear war.” It warned that the North Korean military would “exercise the right to a pre-emptive nuclear attack” to defend the country.

Earlier in the week, the regime warned against joint US-South Korean military exercises due next week, threatening to tear up the 1953 Armistice agreement that ended the Korean War. It declared that, as of next Monday, its armed forces would be free to “take military actions for self-defence against any target any moment.” The North Korean military will also hold its exercises next week.

This reckless posturing by the Stalinist regime is a rather desperate attempt to push for an accommodation with US imperialism. While issuing military threats, North Korean leader Kim Jong-un has engaged in clumsy, diplomatic moves to hint that he might be open to talks with the US. The latest involved a high-profile visit by former American basketball star Dennis Rodman to Pyongyang.

The Obama administration, however, has made clear that it will engage in talks only on US terms—that North Korea abandon all nuclear and missile projects before any consideration is given to ending the American-led diplomatic and economic blockade. US officials have simply dismissed the threat of a North Korean attack on American soil.

South Korea issued strident warnings. Army general Kim Yong-hyun declared: “We have all the preparations for strong and decisive punishment, not only against the source of the aggression and its support forces, but also the commanding element.”

With no prospect of negotiations with North Korea on the horizon, the situation on the Korean Peninsula remains extremely tense. This suits the Obama administration, which is engaged in a comprehensive diplomatic and strategic effort—its “pivot to Asia”—aimed at putting pressure on China and undermining its influence.

The Beijing regime is caught in a quandary. A collapse of North Korea could send a wave of refugees into northern China and also open up the danger of a pro-US regime being established on China’s border. So Beijing continues limited aid and trade with Pyongyang, using this economic relationship as a political lever against North Korea.

At the same time, China is deeply concerned that North Korea’s nuclear tests provide the pretext for the US to maintain large military bases in South Korea and Japan, and also for its anti-ballistic missile shield, which is not primarily directed against North Korea, but against China. Furthermore, Japan and South Korea could seize on the nuclear tests to announce their own plans to build nuclear weapons.

China, along with Russia, voted for the UN resolution and called for its “full implementation”. But China’s UN ambassador, Li Baodong, emphasised the need to restart stalled six-party talks involving the two Koreas, China, the US, Japan and Russia. “The top priority now is to defuse the tension, bring down the heat, focus on the diplomatic track,” he declared.

There are signs of a debate within Chinese ruling circles over its alliance with North Korea. Growing numbers of voices are advocating breaking ties with Pyongyang. Last week, the influential British newspaper, the Financial Times, published an article entitled “China should abandon North Korea,” authored by a prominent Chinese academic Deng Yuwen, deputy editor of Study Times, the journal of the Central Party School of the Chinese Communist Party (CCP).

Deng argued that North Korea had become a liability and possibly even a threat to China if it were to switch sides and cut a deal with Washington. “Basing China’s strategic security on North Korea’s value as a geopolitical ally is outdated,” he wrote. “Even if North Korea was a useful friend during the Cold War, its usefulness today is doubtful.” What was the use of North Korea as “a buffer”, he asked, if North Korea’s nuclear weapons led to a US attack and China was obliged to support its ally.

Deng proposed two solutions: “the best way” being to promote the reunification of the Korea Peninsula and “the next best” being the installation of a pro-Beijing regime in Pyongyang that abandoned its nuclear weapons. Deng’s views are not official policy, but the fact that such inherently risky options are being aired points to deep concerns in Beijing about the danger of North Korea becoming a flashpoint for war on China’s borders.

Far from allaying those fears, the Obama administration is exploiting North Korea’s nuclear program to the hilt to intensify pressure on China and, in the process, heightening the risk of conflict.