(Bloomberg View) -- In conducting yet another nuclear test Friday, North Korea has escalated its confrontation with the rest of the world. The regime celebrated, saying it had made progress in miniaturizing nukes and attaching warheads to missiles. South Korea's president rightly called it an act of "maniacal recklessness."
It's clear, if it wasn't already, that North Korea is no longer just looking for bribes: Its goal is to build a full-fledged nuclear capability. The only prudent response is to harden sanctions in a way that finally gets the country's attention.
Kim Jong Un's regime has been blasting ordnance left and right this year. It conducted a nuclear test in January, launched a long-range rocket in February, fired a ballistic missile off a submarine in August, and sent three more hurtling toward Japan earlier this week.
These alarming pyrotechnics are pushing East Asia toward a new era of instability. They raise the likelihood that Japan and South Korea may seek their own nuclear deterrent, even as tensions with China rise over plans to install missile defenses in the region. They increase the chances of a clash that would draw in the world's two leading powers. And they bring North Korea ever closer to its goal of being able to reach the continental U.S. with a nuclear-tipped missile.
North Korea is likely exaggerating its abilities -- it wouldn't be the first time -- but its weaponry is improving, and this alone ought to concentrate minds.
Are there any sanctions left to deploy? Yes. The United Nations was already mulling stiffer penalties. It could designate more of North Korea's companies for sanctions and more of its operatives for travel and trade blacklists. The U.S. Congress should tighten restrictions on traveling to the North, and the White House should press other countries to stop hiring North Korean laborers whose remittances support the regime.
The Treasury should intensify its efforts to cut off the North's banks and their enablers from the world financial system. This means building a case against Chinese financial institutions, which North Korea uses to procure illicit missile and nuclear technology. China's support in sanctioning those banks would be invaluable, obviously -- but the U.S. should go ahead even if that cannot be secured.
China doesn't want the North Korean regime to collapse, but it ought to see advantages in imposing some restraint. It should help to enforce sanctions already in place, and move against the North's covert weapons trade. Preventing the North from learning how to miniaturize and deliver its weapons should be as urgent a priority for China as it is for the U.S.
China and the U.S. may not be natural allies, but they have a shared interest in taming the world's worst regime.
--Editors: Timothy Lavin, Clive Crook.
For more columns from Bloomberg View, visit http://www.bloomberg.com/view.