TOKYO • With the kind of fanfare that only a totalitarian state can muster, North Korea at the weekend flaunted missiles that can theoretically reach the United States as it tried to demonstrate that its military reach is fast expanding.

Although the missile in yesterday's attempt - like others before it - exploded shortly after launch, experts warn that North Korea's rocket scientists learn something from failures as well as successes, giving them information they can use to hone their technology.

Certainly, the military hardware paraded through Pyongyang on Saturday shows that leader Kim Jong Un is unrelenting in his quest to develop a missile capable of reaching the United States.

Experts were stunned at the sheer number of new missiles on display during the parade - including, apparently, a new and previously unknown type of intercontinental ballistic missile (ICBM).

The two-hour parade took place on a day officially known as the "Day of the Sun", the anniversary of the 1912 birth of Kim Il Sung, North Korea's founder and the current leader's grandfather.

"They are not just showing off missiles that are hard to build," said Dr Jeffrey Lewis, a North Korea specialist at the Middlebury Institute of International Studies in Monterey, California. "They are showing off all the associated technologies you need for credible deployments."

Although experts were continuing to analyse footage from the parade, it appeared that North Korea had shown off a third and previously unknown ICBM.

It appeared to have elements of two other ICBMs, the KN-08 and KN-14 missiles.

"We are totally floored right now," said Mr Dave Schmerler, a research associate at the Middlebury Institute of International Studies.

"I was not expecting to see this many new missile designs," he told the Wall Street Journal.

North Korea has claimed to be able to make nuclear weapons small enough to be able to fit on a missile.

The KN-08 and the KN-14, both with the theoretical capacity to reach the US mainland, had appeared in previous parades, and made their appearances again on Saturday.

The parade included the same vehicles as in the past but, instead of carrying missiles, they carried huge, previously unseen missile canisters.

Those could have contained the KN-08 and KN-14, or something else - or nothing at all.

But the message was clear.

"This was a promise of future capabilities more than a demonstration of existing missiles," said Mr Joe Cirincione, president of the Ploughshares Fund, which tries to stop the spread of nuclear weapons.

"We do not know if there is actually an ICBM in that canister. But it is certainly coming."

Furthermore, the canisters are probably an indication that North Korea is pressing ahead with solid-fuel technology, because canisters are used to keep the temperature stable for solid-fuel missiles.

By using solid fuel, North Korea can roll out its missiles from a hangar or tunnel ready to launch, rather than having to fuel them on a gantry like the older liquid-fuelled rockets. That allows much less time for the missiles to be detected by satellites.

North Korea has been using this technology for its submarine-launched ballistic missile, which Mr Kim boasted was "the greatest success", and the land-based variant, tested earlier this month, but less successfully. Both types of missiles were displayed in the parade on Saturday.

Missile experts said the new capabilities, if confirmed, may increase Pyongyang's options as it seeks to test-launch an ICBM able to deliver a nuclear warhead to the continental US, as Mr Kim indicated in his New Year's address in January.

US President Donald Trump responded after that, posting on Twitter: "It won't happen!"

North Korea has never launched an ICBM but, given how difficult the technology is, it would almost certainly fail on its first test, experts say.

Mr Markus Schiller, a German aerospace engineer who specialises in missiles, also cast doubt on how much progress North Korea was making.

"The Soviets tried to build a solid-fuel missile and it took them more than 15 years to get it up and running," he said. "You don't just get a solid-fuel missile overnight."

But even if North Korea does not yet have the technical capacity to launch a missile capable of reaching the US, it has clearly demonstrated that it has the political will.

"It is alarming that they are pouring so much money and resources into this programme," said Mr Michael Elleman, senior fellow for missile defence at the International Institute for Strategic Studies.

"Eventually, they are going to be successful."

WASHINGTON POST, NYTIMES