(CNN) Donald Trump's national security adviser issued a stark warning the day before the President left Washington for a critical swing through Asia: "We're running out of time."

The risk of military confrontation with North Korea appears to only grow by the week. North Korea is quietly, but aggressively, working to advance its intercontinental ballistic missile program to reach the United States with a nuclear warhead. And while the US, its allies and even its adversaries agree more must be done -- and quickly -- there is no clear consensus on how to proceed.

That sobering backdrop makes Trump's 13-day trip through the region -- where he will meet with key players and get a firsthand view of the North Korean nuclear threat -- the United States' best chance to stave off a crisis that is threatening to embroil the US in its first major war in Asia since the Vietnam War.

While there is little expectation that Trump will return to Washington having cracked the code to stopping North Korea's advance, he is under considerable pressure to deliver a clear and consistent message on the US approach to the North Korean crisis. He needs to rally US allies and intends to crank up more pressure on China to change its isolated neighbor's course.

And, as Lt. Gen. H.R. McMaster warned, the clock is ticking. CNN learned earlier this week that North Korea is working on an advanced version of its existing KN-20 intercontinental ballistic missiles that could potentially reach the United States, and it is entirely possible that next year, Pyongyang could master the technology to tip such a missile with a miniaturized warhead.

That means that the current visit could be the last trip by a US president to see the region's leaders face to face before that fateful threshold is crossed.

What's the US strategy?

For now, the President has often left the region befuddled about the US strategy to resolving the crisis. Is that approach best exemplified by his explosive rhetoric threatening "fire and fury"? Or is it rooted in the quiet, cautious diplomacy embodied by Secretary of State Rex Tillerson and supported by Defense Secretary James Mattis?

"It is important the President ... bring forth a clear message that is not contradicted by his Cabinet members. You've got Tillerson talking diplomacy, you've got the President talking military action and personal insults," said Bill Richardson, the former US energy secretary, ambassador and repeat US envoy to North Korea. "And he has to get a common strategy among our allies. We're divided."

And yet just as Trump's most crucial task will be to express the United States' stance clearly, cogently and without contradiction, it is Trump's penchant for impulsive and bellicose rhetoric that is leaving the region most on edge.

Trump is touching down on the heels of a salvo of anti-North Korea sanctions and other pressure tactics that have earned his administration plaudits from US allies in the region. Former US officials and regional experts agree that the administration has delivered the furthest-reaching sanctions yet and needled China toward its most significant actions against North Korea to date.

But those who praise his administration's work to beef up the diplomatic pressure campaign are just as quick to criticize Trump for the ways in which he has undermined those efforts -- and they worry the President could similarly undermine the careful choreography and delicate diplomacy prepared by his own advisers with the stroke of a tweet or an off-script comment while in the region.

Joseph DeThomas, a 30-year veteran of the US Foreign Service and expert in nuclear nonproliferation said he believes the Trump administration has "done very well at increasing the pressure on North Korea," but said he worries Trump's visit to the region could leave the US efforts worse off.

"It's the first time in my life -- having served every president since Jimmy Carter -- that I'm saying, 'Oh, please don't let the President go,' " DeThomas said. "I don't see a lot of good coming out of this and I see lots of risk of an unfiltered comment generating lots of consequences."

Allies on edge

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Trump's past comments have already put US allies on edge.

He has publicly scorned his secretary of state's efforts to open diplomatic channels with North Korea, threatened North Korea with hostile rhetoric and left diplomats stunned by calling Kim Jong Un "Rocket Man" in a United Nations speech where he also threatened to "totally destroy" North Korea.

The stakes are even higher as Trump will spend his first three stops in Tokyo, Seoul and Beijing, less than 1,000 miles from Pyongyang -- where his threats could have a much more serious impact.

Richardson, a sometime-envoy to North Korea, recalled officials there being "really upset" after President George W. Bush privately disparaged the country's then-leader Kim Jong Il as a "pygmy."

"The worst thing you can do is insult them," Richardson said.

The analysis -- though echoed in near-unison across the political spectrum -- is rejected by the White House, which signaled ahead of the trip that Trump has no plans to cool his rhetoric.

"I don't think the President really modulates his language. Have you noticed him do that?" McMaster, Trump's national security adviser, said Thursday. "What's inflammatory is the North Korean regime and what they're doing to threaten the world."

"I think there would be a grave danger if that regime didn't understand our resolve, the President's resolve to counter North Korean aggression," he added.

But instead of threats, experts hope Trump will focus on putting forward a united front between the US and its key allies in the region, Japan and South Korea.

"He needs to hold our allies close, and that in particular means South Korea," said Christopher Hill, who frequently negotiated with North Korean officials as the former assistant secretary of state for East Asian and Pacific affairs and is a former US ambassador to South Korea.

Hill and others worry that Trump will once again accuse Seoul -- where millions already live within reach of North Korea's nuclear arsenal -- of "appeasement" or again raise the possibility of terminating the bilateral free trade agreement between the two countries, known as KORUS, which could weaken ties between the two countries at a critical juncture.

Trump in China

But the President's most crucial visit will be to China, which the Trump administration believes holds the key to convincing Kim to give up his ballistic missile and nuclear programs.

"China is definitely doing more, but obviously it's not enough, until all of us achieve denuclearization," McMaster told reporters on Thursday, a nod to the US desire for China to further tighten the noose on North Korea, especially when it comes to energy sanctions.

While China -- which accounts for 90% of North Korea's foreign trade -- could take further steps to weaken its neighbor economically, many China analysts believe that Beijing's leverage over Pyongyang is not as significant as Washington thinks, given that Kim appears to believe that the only way his regime will survive is the acquisition of the capability to deliver a nuclear weapon to the US mainland.

And ultimately, China's own strategic interests -- in preventing the collapse of North Korea, and a united Korea that might ally itself to the US -- may outweigh its incentive to help the Trump administration out of a tight spot.

"This is something in which it's hard to see where this is going -- will this push the Chinese to resolve a problem that the US expects it to help resolve?" said Leland Miller, a senior fellow at the Atlantic Council. "I think the answer to that is unfortunately, no."