In North Korea it’s called the “Day of the Sun”. Yesterday, April 15 marked the anniversary of the birth of the country’s founding president Kim Il Sung, grandfather of the country’s current leader Kim Jong-un.

On Thursday foreign journalists visiting the country for the annual commemoration were told to prepare for a “big and important event.”

North Korean officials gave no details as to the nature of the event or where it would take place, and in the past similar announcements have been linked to relatively low-key military set pieces.

But these are different and dangerous times. Satellite images show signs that North Korea is preparing another nuclear test. Donald Trump is President of the United States. A US Navy strike group led by the aircraft carrier Carl Vinson is moving towards the Korean peninsula and on Friday, China’s Foreign Minister Wang Yi warned that “conflict could break out at any moment”.

Difficult as it is to imagine, there is the threat of a possible nuclear war.

“We’re prepared to respond to an all-out war with an all-out war,” said Choe Ryong-hae, believed to be North Korea’s second most powerful official.

“We are ready to hit back with nuclear attacks of our own style against any nuclear attacks,” he warned yesterday.

The potential trigger to that war is whether Kim Jong-un chooses to carry out another nuclear weapons test.

In the eyes of Washington such a move would be a provocation, the crossing of a red line laid down recently by the United States insisting North Korea curb its nuclear programme.

Once again all eyes are focused on the 38th parallel of latitude that formed the border between North and South Korea prior to the Korean War. This is a conflict that technically has never really ended given that the north only ever signed a truce in 1953 not a peace treaty.

This weekend the region is in nervous limbo fearing an escalation in tensions on the ‘parallel’ that China warned might be heading towards an “irreversible and unmanageable stage.”

So just how dangerous is the situation, and what would the early warning signs be of impending military action leading to a catastrophic all out war?

First and foremost, everything depends on whether the North Korean government in Pyongyang make the high-risk decision to follow through on another nuclear test.

Satellite imagery from Wednesday released by 38 North a US North Korean affairs website, showed continued activity at a nuclear test site in North Korea, noting movement of people and vehicles around the area, indicating possible preparations for the testing of a nuclear weapon.

On Friday the country's foreign minister said in an interview that Pyongyang would forge ahead with the test “whenever supreme headquarters sees fit.”

Many analysts believe however that a delay to the test carries risks of its own for North Korea in that it might embolden the United States and provide an opportunity for a punitive strike.

Yesterday phalanxes of military bands and goose-stepping soldiers marched through Pyongyang’s main Kim Il-sung Square for the “Day of the Sun” celebrations, as a black-suited Kim Jong-un watched on.

Kim’s high profile presence at the huge military parade suggests that perhaps the situation has not yet reached the point where military action is imminent. In such a scenario the leader would almost certainly reduce his visibility and go to ground.

Observers are also watching for other ‘red flag’ warnings that military action might be about to take place such as defensive preparations near the North-South Korean border and a shutdown at China’s border.

While South Korea's acting president Hwang Kyo-ahn has ordered his military to intensify preparations, reports have yet to surface that the country is bolstering security at the frontier.

China however appears to be mobilising troops along its own border while Air China, one of two airlines with services to North Korea, has announced that it is cancelling flights to the country starting from tomorrow.

This could of course simply be a result of Beijing proving its willingness to ramp up economic pressure on North Korea or low passenger turn out, but such signs if precautionary would be crucial indicators of a shift in Chinese posture over the crisis.

For its part the signs from Washington of impending military action might be suggested by any changes in the itinerary of US Vice President Mike Pence's 10 day tour of the Asia-Pacific region, during which he is scheduled to celebrate Easter with US forces in South Korea.

For now the situation is incredibly tense and one wrong move could plunge the crisis into the abyss of military action.

Should that worst-case scenario occur then the Trump administration would be faced with what Pyongyang described as a “merciless” response.

For the moment neither side shows signs of backing down and the build up of firepower and tough talk escalates by the day.

Already US Secretary of State Rex Tillerson has said that when it comes to the North “all of the options are on the table”.

Trump himself meanwhile recently tweeted that “North Korea is looking for trouble”, and that if China, North Korea's only major ally, declined to address the problem of North Korea's growing nuclear arsenals, “we will solve the problem without them! U.S.A.”

Trump has talked of “an armada” of US warships en-route, disclosing that submarines are part of the group.

“We have submarines,” he said. “Very powerful. Far more powerful than the aircraft carrier. That I can tell you.”

But just what exactly is the range of military options the US is likely to weigh up?

On the lowest end of the scale, the US could launch a punitive strike limited to a single base or facility in the country, with the threat of further action down the line if Pyongyang doesn't alter its behaviour.

Though this kind of attack offers the best way to keep the situation from escalating, it would by no means ensure that North Korea heeds American warnings and eases up on its nuclear and missile development.

Nor does it eliminate the risk that Pyongyang may respond to the strike in kind. According to the independent US based open intelligence group Stratfor, if Washington judges that Pyongyang is likely to launch a counter-attack regardless, it may decide that the most prudent course of action would be a comprehensive campaign to degrade or eliminate North Korea's retaliatory capacity.

“This scenario would best position the US and its allies against a North Korean response, but it would entail significant risks, virtually guaranteeing full-blown war on the Korean Peninsula,” Stratfor analysts concluded.

Perhaps the biggest danger in the current crisis is the uncertainty and unpredictability of the protagonists. Could it be that the “big event” Pyongyang speaks of is nothing more than yesterday’s massive celebratory parade or does Kim indeed want to throw down the gauntlet with another nuclear test firing?

Then there is the unpredictability of Trump himself.

“For allies, enemies, and observers alike, Trump appears to be a wild card, and self-avowedly so,” was how Kathy Gilsinan who heads up the global section at The Atlantic magazine summed up the president recently.

“Even foreign-policy positions that are “predictable” for an American president - condemning the use of chemical weapons in war, say, or not deriding Nato as obsolete - were unanticipated reversals from this particular president,” Gilsinan points out.

Trump himself, of course, has said that America needs to be more “unpredictable.” For now certainly his foreign policy moves have proved to be just that.

Far from being ‘isolationist’, as he insisted the US would be during his presidential election campaign, the evidence on the ground now points the other way.

What we are witnessing right now, is a dramatic escalation in the militarisation of US foreign policy in the Middle East, Africa, and Afghanistan, says the perceptive analyst and writer, Ahmed Rashid, whose recent book ‘Descent into Chaos’, chronicles Western mistakes and the rise of Islamist extremism.

Events in North Korea this weekend only underline that escalation making it apparent in Asia now too.

In what he identifies as Trump’s “military-first strategy”, Rashid cites a number of examples of this rise in military interventionism.

He flags up how a few weeks ago, US aircraft carried out over 30 air strikes against Islamic militants in Yemen, almost the same as the number carried out there all last year.

Then there are rising US troop movements. Some 400 US soldiers are en-route to Syria to set up an artillery base to retake the city of Raqqa held by Islamic State (IS) fighters. Another 1,000 may soon be sent to Kuwait as a reserve force. Another 400 have gone to Iraq and some 8,000 will go to Afghanistan.

It was in Afghanistan too earlier this week that the US dropped the largest non-nuclear bomb ever used in combat, the GBU-43/B Massive Ordnance Air Blast bomb (Moab) - aka the Mother of All Bombs - on a base used by Islamic State (IS) extremists.

Some viewed the strike as a warning to Kim Jong Un, and an attempt for the Pentagon to steer him away from any provocative actions.

“I don’t know if this sends a message, it doesn’t make any difference if it does or not,” Trump said at the White House on Thursday. “North Korea is a problem, the problem will be taken care of.”

Supporters of Trump have said his ‘carte blanche’ authorisation for the US military to carry out such strikes is a new approach to using military power.

Trump appears to have reverted to a dangerous dependency on the military. At home, he has proposed cutting the State Department and foreign aid budgets by a third to fund a $54 billion increase in the military budget.

Much of this escalation of US military intervention meanwhile has barely registered on the international radar. Until now with the exception of the high profile crises in Syria and North Korea much of it has gone on largely unannounced and been quietly incremental.

As Ahmed Rashid points out, this is quite an active policy, for someone like Trump who claimed during his election campaign to have no interest in such overseas military adventures and campaigns.

There is concern too that much of this military activity is taking place often without due consultation with Nato or other US allies.

Equally worrying is that it’s being conducted with little or no tandem diplomatic efforts.

“Trump’s emphasis on war isn’t balanced by any interest in peace-keeping. There is no hint of US diplomatic initiatives in conflict zones,” Rashid highlighted recently.

This weekend as the crisis in the Korean peninsula intensifies, Washington’s ally South Korea is understandably concerned that the Trump administration could launch an attack on the north without consulting with their counterparts in the South Korean government. Rumours of an imminent war have swirled on social media, leading government officials to speak out, trying to keep the situation calm.

On Tuesday, Cho June-hyuck, a spokesman for South Korea's Ministry of Foreign Affairs, said in a regular press briefing that the US would not undertake military action without first consulting Seoul.

While the US has given such assurances, there is still great nervousness in Seoul that Trump might not stick to his promises.

Moon Jae-in, a liberal frontrunner for South Korea's May 9 presidential election, addressed the tensions in a post on Facebook over the last few days.

“South Korea's security is as important as the US' security. Therefore, there must be no pre-emptive strike without South Korea's consent,” Moon wrote.

Yesterday next to the Taedonggang River that flows through Pyongyang, the North Korean military parade that marked the Day of the Sun was so massive it prompted one BBC reporter to remark that; “You can feel the ground shake.”

The world for now will continue to hold its breath. The hope must be that the Day of the Sun is not followed by the flare of a nuclear burst, or that the ground shakes with the sounds of war.