North Korea's latest overwrought and cartoonish rhetoric issued today, a promise of "thousands-fold" retaliation against the United States for punishing trade sanctions approved by the United Nations Security Council over the weekend, is oddly comforting. The U.S.-sponsored resolution, which passed with unanimous support from all 15 council members, is going to hit Kim Jong-un where it counts, denying the country an estimated $1 billion in exports or about one-third of its total trade with the outside world. Leadership in Pyongyang will be left to ponder: What hurts most, the economic deprivation or the manner in which the world is united against North Korea's nuclear ambitions?

If President Donald Trump is going to extend kudos (he wrote on Twitter Sunday that he was "impressed" by the UN action), he ought to direct them toward China, North Korea's most important trading partner.


Mr. Trump had been urging Chinese leadership to take a more active role in pressuring North Korea over its nuclear program. Whether that pressure was a factor in China's willingness to support the resolution is hard to tell. Most likely, President Xi Jinping recognized that he can't continue to be North Korea's economic enabler and promote his own country's trade interests.

Still, this is a legitimate diplomatic victory for the Trump administration, albeit an incremental one. The question now is what will the U.S., South Korea and others in the region accept from North Korea in return for restoring coal, iron, lead and seafood exports and allowing more North Koreans to work abroad? Hardliners will most likely insist Mr. Kim agree to abandon further intercontinental ballistic missile development and give up nuclear weapons entirely, but the prospects for that are doubtful. Even robust trade sanctions are unlikely to prove effective given the country's history.

North Korea vowed Monday to bolster its nuclear arsenal and launch "thousands-fold" revenge against the United States in response to tough U.N. sanctions imposed after its recent missile tests

Would the Trump administration settle for something closer to China's preferred course, a freeze on further nuclear or missile testing by North Korea as well as a freeze on further military escalation in the region by the U.S. and South Korea as an entree to direct negotiations? That seems unlikely, too. All of which suggests that the sanctions will hurt but not necessarily halt North Korea's nuclear ambitions. If that sounds familiar, it should. There's a reason why isolating North Korea has been a longstanding, if mostly ineffective policy — it's simply the only reasonable option available.

North Korea vowed Monday to bolster its nuclear arsenal and gain revenge of a "thousand-fold" against the United States in response to tough U.N. sanctions.

That doesn't mean sanctions are certain to fail. At minimum, they'll need time and enforcement and that requires the sort of discipline, international cooperation and unity that isn't the Trump administration's strong suit. Secretary of State Rex W. Tillerson has generally been a voice of reason on this issue, telling world leaders that the U.S. isn't interested in regime change and, as recently as Sunday at ASEAN talks in Manila, suggesting that North Korea could promote direct talks simply by discontinuing its missile launches. But does Mr. Tillerson have a free hand in this or will any diplomatic progress be eventually sabotaged by an early-minute tweet-storm from the White House tossing red meat at is hard-right core followers?

China's action can't be judged in isolation. As welcome as its tougher stand against North Korea may be, China's world influence is on the rise thanks, in part, to the Trump administration's abandonment of the Trans-Pacific Partnership trade agreement. The U.S. has lost its trade clout in Southeast Asia, and China is happily filling the void. Remember all that fuss about China's aggressive territorial claims in the South China Sea in recent years? Its neighbors' concerns seem to be softening. The South China Sea code of conduct discussed at the Association of South East Asian Nations talks (which amount to an outline for further "consultations") are somewhat underwhelming given China's actions to date.

China, Pyongyang's major benefactor, urged its outcast neighbor Sunday to make a "smart decision" and stop conducting missile launches and nuclear tests.

Indeed, it's fair to wonder if China isn't the biggest winner in the U.N. sanctions decision. It collects international goodwill by taking action the country's leadership should have taken years ago. And it gives President Xi another bargaining chip if the U.S. presses him on trade issues such as intellectual property rights, technology transfer or currency manipulation in the future. What's the loss of trade with North Korea compared to the economic bounty available in the west? If tensions around North Korea de-escalate, so much the better.

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