North Korea test-launched another missile Friday that arced over northern Japan and into the Pacific, showing its progress toward being able to strike the U.S. and signaling its defiance of U.N. sanctions imposed after its sixth, and most recent, nuclear test earlier this month.

"The world will never accept a nuclear-armed North Korea," U.S. Ambassador Nikki Haley told the U.N., after the sanctions passed the Security Council on Monday. She added: "If the North Korean regime does not halt its nuclear program, we will act to stop it ourselves."

But some analysts believe that this approach to the North Korean nuclear crises is dangerously deluded.

A decade or so ago, it still may have been possible to use sanctions or the threat of military force to compel North Korea to give up its nuclear programs, argues Zhao Chu, an independent, Shanghai-based analyst, former soldier and former editor of World Outlook, a foreign affairs magazine.

But Zhao warns that the situation has now fundamentally changed, and that trying to fly through a window of opportunity that has already closed is a very bad idea. Pyongyang can hardly be expected to give up the nuclear ace in the hole that it worked so long to acquire.

Then again, perhaps the window of opportunity for military action was never open, argues Lyle Goldstein, an associate professor in the Strategic Research Department at the U.S. Naval War College in Newport, Rhode Island. This is because the South Korean capital, "Seoul was always so vulnerable" to North Korean conventional artillery attacks, which could cause mass casualties.

Analysts say North Korea looked at the fate of other authoritarian regimes, particularly Libya under Moammar Gadhafi and Iraq under Saddam Hussein, and concluded that their lack of nuclear weapons left them vulnerable to being toppled by the U.S. and its allies.

Pyongyang now believes — correctly or not — that, by acquiring the ability to carry out a nuclear strike against the U.S., it has taken a crucial step toward assuring its own survival.

"You could credit the Kim regime with taking regime change off the table," says the U.S. Naval War College's Goldstein.

Another way of looking at it is that North Korea has now gained a valuable bargaining chip. And while it is unlikely to give it away for nothing, it may be willing to trade it for some sort of security guarantee, or some form of payment, whether in food or energy.

A grimmer possibility, of course, is that it might just sell it to raise much-needed cash.

Here, Goldstein sees an opportunity to strike a bargain with North Korea to resolve the crisis. He says that years of using all sticks and no carrots have not yielded the required results, and it's time for some creative thinking.

Goldstein rejects the idea that the only way to improve North Korea is through regime change. "There are plenty of obnoxious regimes around the world," he says, "and more than a few are allies of the United States."

The mainstream argument against negotiating with North Korea, says Goldstein, is that you can't reward bad behavior.

"But that's more appropriate to dealing with school children than nations in the nuclear era," he says.

Goldstein and other advocates of making a deal with North Korea point to a 1994 bargain reached during the Clinton administration, and known as the "Agreed Framework."

Its opponents say the bargain's eventual collapse shows that North Korea can't be trusted to keep its word. Its proponents, including Goldstein, say that the U.S. shares some of the blame for the deal's ultimate failure.

When not threatening to unleash "fire and fury," as President Trump put it, on Pyongyang, the U.S. has also stated it is "interested in finding a way to get to a dialogue," in the words of Secretary Of State Rex Tillerson.

President Trump has even said, Goldstein notes, that "he would sit down and have a burger with Kim."

Goldstein agrees with Zhao that cooperation with China is crucial to resolving the issue: "It's well past time to try new approaches, and that means," he says, that the US should be "following China's lead."

He says the U.S. should consider China's suggestion to halt military exercises with South Korea, in exchange for North Korea freezing its nuclear and missile tests.

He even suggests that Russia or China could send troops to North Korea to provide a security guarantee that might help to convince Pyongyang it doesn't need nukes.

Goldstein admits that mainstream analysts often accuse him of going too far in appeasing or accommodating China. But he says accusations of the sort leveled at him are "injurious to careful thinking about interests and about how we find peaceful solutions to these problems."

Independent analyst Zhao Chu, meanwhile, is less sanguine about the prospect of talking Pyongyang out of its nukes.

Zhao argues that Washington and Beijing's failure to cooperate on the North Korean nuclear crisis has given Pyongyang the time and space it needs to achieve its nuclear ambitions.

Part of the problem, he says, is that the U.S has outsourced the North Korea problem to China, expecting Beijing to solve it by sanctioning Pyongyang.

But Beijing will not implement sanctions so severe that they cripple Pyongyang, Zhao says. This is because Beijing "will not allow what it understands to be a dispute between the U.S. and North Korea to become a dispute between North Korea and China."

Another problem is that Chinese and Americans who see each other as their main security threat both see North Korea as, if not a physical buffer, at least a useful trap, hindrance or distraction for their rival, in a zero-sum game.

Domestic critics, including Zhao, also have argued that Beijing's simultaneous efforts to keep relations with Washington and Pyongyang from falling apart are becoming increasingly untenable.

Publicly, the U.S. and China both say they want the same thing: a nuclear-free Korean Peninsula. The difference, though, Zhao says, is that the U.S. is not averse to regime change in Pyongyang, if it eliminates the nuclear threat. But that regime change is unacceptable to Beijing. Conversely, Beijing would rather have a stable, nuclear-armed neighbor than a nuclear-free but hostile regime on its doorstep.

"I think we should take a pragmatic attitude and tolerate a nuclear North Korea," Zhao concludes. "Why did the U.S. and China tolerate India and Pakistan going nuclear? Because they had no better options."

All that's left to do, Zhao says, is to try to prevent North Korea from proliferating nuclear technology, help it to avoid nuclear accidents, and set up unofficial dialogues to get scholars, if not officials, discussing possible solutions.

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