TOKYO (AP) -- Despite North Korea's claim its intercontinental ballistic missile launch shows it can attack targets anywhere it wants, experts say it will probably be years before it could use such a weapon in a real-world scenario.
 
The test on Tuesday demonstrated the North is closer than ever before to reaching its final goal of developing a credible nuclear deterrent to what it sees as the hostile policy of its archenemies in Washington. 
 
But even for an experienced superpower, getting an ICBM to work reliably can take a decade.
 
Launching a missile under test conditions is relatively easy. It can be planned and prepared for and carried out whenever everything is ready, which makes success more likely. The real game-changer would come when the missile is considered operational under any conditions -- in other words, when it is credible for use as a weapon.
 
For sure, the North's Fourth of July fireworks were a major success. 
 
Initial analyses indicate its new "Hwasong 14" could be capable of reaching most of Alaska or possibly Hawaii if fired in an attacking trajectory. It was instead shot at a very steep angle, a technique called lofting, and reached a height of more than 2,500 kilometers before splashing down in the Pacific Ocean 930 kilometers away.
 
Hwasong means "Mars."
 
"If a vague threat is enough for them, they could wait for another successful launch and declare operational deployment after that, and half the world will believe them," said Markus Schiller, a leading expert on North Korea's missile capabilities who is based in Germany. "But if they take it seriously, as the US or Russia do, it would take at least a dozen more launches and perhaps 10 years. Mind you, this is their first ICBM."
 
Schiller noted the example of Russia's latest submarine-launched missile, the Bulava.
 
"They really have a lot experience in that field, but from first launch to service it took them almost 10 years (2004 to 2013)," he wrote in an email to The Associated Press. "They still have troubles -- one of their test launches just failed."
 
The bar for having an operational ICBM is also higher for the North if the United States is its target.
 
An ICBM is usually defined as a land-based ballistic missile with a range in excess of 5,500 kilometers. That comes from US-Soviet disarmament talks and in that context makes good sense. The distance between Moscow and New York is about 7,500 kilometers.
 
But Narushige Michishita, a defense expert and professor at Japan's National Graduate Institute for Policy Studies, pointed out that although the range required for North Korea to hit Alaska would be 5,700 kilometers and Hawaii 7,500 kilometers, reaching the other 48 states requires ranges of 8,000-12,000 kilometers.
 
"In the US-DPRK context, the 5,500 kilometer-range ICBM means nothing," he said. "We must take a look at the range, not the title or name."
 
Pyongyang made a point of trying to dispel two big questions about its missiles with the test: re-entry and accuracy.
 
It claims to have successfully addressed the problem of keeping a nuclear warhead intact during the descent to a target with a viable heatshield, which would mark a major step forward. The Hwasong 14 isn't believed to be accurate enough to attack small targets despite Pyongyang's claims otherwise, but that isn't a major concern if it is intended to be a threat to large population areas, such as cities on the US West Coast.
 
The reliability problem, however, remains. 
 
"These missiles are very complex machines, and if they're launched again tomorrow it might blow up on the pad," said David Wright, co-director and senior scientist at the Global Security Program of the Union of Concerned Scientists. "You don't want to do that with a nuclear warhead on top."
 
Wright said he believes Kim Jong Un decided to start a number of different development programs for different missile systems a couple of years ago and that the frequency of launches over the past 18 months suggests those programs have moved forward enough to reach the testing stages.
 
"I have been surprised by how quickly they have been advancing," he said.
 
Wright said the North is believed by most analysts to have a nuclear device small and rugged enough to be put on a long-range missile, or to be very close to having one.
 
But he said it remains to be seen if its latest missile can be further modified to get the range it needs to threaten the contiguous US, or whether that would require a new system with a scaled-up missile and more powerful engine.
 
"I suspect that latter, but don't know yet," he said.
 
The answer to that question matters because it has implications for how long it will take North Korea to really have an ICBM that could attack the US West Coast -- and how long Washington has to take action to stop it.
 
What is Wright's estimate? 
 
"I would expect a couple years," he said.