AFP PHOTO / KCNA VIA KNS This picture, taken by North Korea's official Korean Central News Agency on March 7, 2013 shows North Korean leader Kim Jong Un (C) inspecting the Mu Islet Hero Defence Detachment near South Korea's Taeyonphyong Island in South Hwanghae province, North Korea's southwestern sector of the front.

In 17 years under Kim Jong Il, North Korea grabbed the world’s attention with several missile tests, a pair of nuclear detonations and a big helping of threats. Kim’s youngest son and successor has hit all those highlights of North Korean-style leadership in just over a year at the helm. And while these acts and the rhetoric that surround them sound familiar, their tempo has clearly quickened, particularly this past week as the Pyongyang regime responds to the latest round of U.N. Security Council sanctions in response to its Feb. 12 nuclear test.

In recent days North Korea has said it will drop its recognition of the armistice that ended hostilities in the 1950-53 Korean War and threatened to carry out a preemptive nuclear strike against U.S. “aggressors.” On Friday North Korea warned it was pulling out of all non-aggression pacts with the South. Pyongyang has said it might ignore the 1953 cease-fire several times before, but the nuclear threat is a new level of escalation. While North Korea doesn’t possess the sort of reliable long-range missiles or miniaturized nuclear devices that would allow it to hit the U.S., its capabilities are improving, as shown by its successful satellite launch in December.

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“One has to take what any government says seriously,” U.S. State Department spokesperson Victoria Nuland said Thursday. “It’s for that reason that I repeat here that we are fully capable of defending the United States. But I would also say that this kind of extreme rhetoric has not been unusual for this regime, unfortunately.” In South Korea, new president Park Geun-hye was far less sanguine about the North Korean threat. “Our current security situation is very grave,” Park warned Friday at a commissioning ceremony for graduating military cadets, the Yonhap News Agency reported. South Korea’s military has responded in kind to the North’s rhetoric, warning that a nuclear attack would lead to the North’s destruction.

The sanctions unanimously approved Thursday by the U.N. Security Council ban transactions that might help North Korean nuclear proliferation and require governments to inspect shipments to or from the North that might contain prohibited weapons or related materials. The measures also block the sale to North Korea of some luxury items like yachts and luxury cars and call for increased monitoring of North Korean diplomats to prevent them from aiding their country’s weapons programs. International relations expert Marcus Noland writes on the Peterson Institute for International Economics’ North Korea: Witness to Transition blog that while the sanctions do offer new powers to control North Korean proliferation, there’s also plenty of wiggle room:

The problem with these latest steps is that each has a kind of “credible information” clause. A government that does not want to enforce them can say that they lack credible information, or that the information that they were provided did not meet the standard of “reasonable grounds.” On the other hand, the resolution also provides cover for a campaign to intensify financial restraints on the country on the grounds that virtually all of its external transactions ultimately feed back into a central pot from which the country’s excessive military expenditure is drawn. Expect continuing diplomacy from the US and its allies to secure support for an expansive definition of proscribed trade and financial transactions.

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The pivot on which all North Korea questions turn is, as ever, China, its neighbor and only major ally. China backed the passage of the new sanctions, and the latest missile launch and nuclear test came in the midst of an important political transition in China. The new leadership team of Xi Jinping and Li Keqiang can hardly be amused. Despite that, China’s fundamental strategic calculations remain the same, North Korea expert Andrei Lankov argues in a recent essay. “All things considered, China tends to see a nuclear North Korea as the least unacceptable option,” he wrote.

Other observers say that China may be rethinking its position. Paul Haenle, director of the Carnegie-Tsinghua Center for Global Policy in Beijing, wrote last month that North Korea’s actions are undermining China’s international image and entangle its leaders in growing regional tensions. “I do sense in my interactions with Chinese officials and experts a growing concern over Kim Jong Un and his ability to lead the country,” says Haenle, who was the U.S. National Security Council China director from June 2007 to June 2009 and White House representative to the six-party Korean denuclearization talks. Any changes will be quiet, he says. “I don’t expect overnight any major sort of 180 degree change in China’s policy and I don’t expect it to be done in any sort of public, loud way, but what we could potentially see is a shift back to where they were at end of the Bush administration, where they put conditions for aid and assistance and even high-level interactions on progress in the denuclearization track to prevent North Korea from provocations and destabilizing actions.” China eased its carrot and stick approach after Kim Jong Il suffered a stroke in mid-2008, Haenle says, because it was clear the country was going into a leadership transition.

If China’s endorsement of the latest sanctions are a sign it is growing weary of its North Korean ally, it has been at pains to deny it, with the Ministry of Foreign Affairs saying it continues to advocate stability and denuclearization. “I don’t think China has changed its stance,” says Fang Xiuyu, a North Korea expert and professor of international studies at Fudan University in Shanghai. “China’s position on the North Korean nuclear crisis is very clear: support denuclearization and maintain regional peace.” The new sanctions are “an international consensus and we have no reason not to support them.” Now the question is if they’ll have any effect.

—with reporting by Gu Yongqiang/Beijing

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