This week, the United States and its ally South Korea began large-scale military exercises, and North Korea responded by threatening "merciless retaliation". This follows Pyongyang's recent back-and-forth over whether to strike Guam and President Trump's warning that North Korea was facing a future of "fire and fury".

Not surprisingly, people are a little worried. I received an email from an old high school friend. We had not corresponded in a while. The email comprised two words: "Save us".

My friend knows that I have worked on North Korea and nuclear weapons for more than 15 years and that I have, in fact, been to the DPRK (Democratic Republic of Korea) to discuss nuclear policy.

"I'm on vacation in Maine. You're going to have to handle this one," I replied with a smile.

He wasn't the only one asking. Facebook friends, journalists, relatives. There was even a guy at the Home Kitchen Cafe in Rockland, Maine who recognised me and asked a waitress to approach me on his behalf. I walked over, and we chatted for a minute. He explained that he thought it was a bad time for the US and South Korean military exercises before returning to his Reuben sandwich.

To no one's surprise, I can't "save us", but I can give you a sense of where things stand, where they might be going, and a few things we might want to do. Consider this the inside scoop from that high school buddy who happens to be a nuclear weapons and North Korea expert.

"How dangerous have things gotten? Are we about to get into a war?"

No, we are not about to get into a shooting war with the North Koreans - or at least probably not. Well, not for now, anyway. The military exercises and President Trump's impromptu threats do not suddenly make a military conflict more likely today than it was last month or last year. In history, major wars - not nuclear wars, just plain old large-scale, bloody conventional wars that kill millions of people - don't happen every day. Big wars like WWI or the Korean War - and nuclear wars - are low probability, high consequence events. They don't happen very often, but when they do …

And for the most part, the fundamentals have not changed. Secretary of Defense James Mattis is correct to say that the US and South Korea maintain an overwhelming military advantage over North Korea. If war were to break out, North Korea would lose and lose badly. It would be the end of the Kim Jong-un's regime, and the one thing Chairman Kim wants is to remain in power.

OPINION: Why a war with North Korea is unlikely

That does not mean the situation is set, let alone stable. Pyongyang is on a course to develop a nuclear missile that can hit the US homeland. Though it's not quite there yet, at their current pace of testing, that day is coming sooner rather than later. Obviously, that would be an unwelcome development, but it won't be any different from the situation our treaty allies Japan and South Korea and the 80,000 US troops and their families who live there have been facing for some time now. And it's worth remembering that, today, Russia and China have nuclear weapons aimed at American cities - just as the US has their nuclear weapons pointed at them - and have so for decades. So it's not a good situation, but it's not a totally new one either.

"But if North Korea doesn't want to attack us with nuclear weapons, why are they rushing as fast as they can to build them?"

That's a great question, and it's tough to answer. It can be hard to judge the intentions of an adversary, but it is even more challenging in the case of North Korea, arguably the most closed country on the planet. North Korea's official policy consists of two parts: become an accepted nuclear weapons state and build its economy. Why nuclear weapons? Analysts differ. Some argue that Pyongyang honestly fears that the US seeks regime change, and by their calculation, the only way to ensure survival and avoid the fate of Iraq's Saddam Hussein is to possess the ultimate weapon. Others argue that North Korea wants nuclear weapons for bargaining. Still others think Pyongyang will use nuclear weapons as military cover for new provocations.

I don't think we really know, and their thinking may have changed over time. What we do know is that Chairman Kim controls the country, he doesn't plan on giving that up anytime soon, and a war would put that in jeopardy.

"So everything's OK, then. It's not as crazy-dangerous as it seems, right?"

Actually, that's not true either. It's crazy-dangerous.

The bluster and bluffing by both the US and the North Koreans have increased the chances of conflict, including nuclear war. The odds may still be low, but they are now greater than they were before, and if there is anything people should have learned over the last year is that "improbable" does not mean "impossible". Improbable events actually happen - just not as often as other events.

An agreement that would freeze testing would not mean an end to the North's weapons programs, but it will stop them from progressing further at a moment when they are on the verge of developing a nuclear capable intercontinental missile (ICBM).

So while no country wants to commit suicide by launching a war they know they will lose, leaders can make mistakes. They can miscalculate or misperceive the situation and take actions that precipitate a war that neither side actually wants. What feeds miscalculation and misperception, you may ask? Bluster and bluffing.

Mr Trump's threat to attack North Korea if they made more verbal threats was called by the young Mr Kim in fewer than 24 hours, when North Korea announced new plans to attack Guam. The US response was neither fire, nor fury. Pyongyang followed by announcing it would take a position of "wait and see" on the eve of yet another round of US-South Korea military exercises.

Absent some change, there are certain to be more missile tests and perhaps a nuclear test. So what happens the next time, a month from now or a year from now when the American leader makes a threat - a serious threat that he intends to carry out? Will Kim believe it, or will he err and think it's posturing.

Alternatively, we may find ourselves in a real crisis with North Korea, following some naval incident or the shelling of an island. President Trump might make a threat he does not intend to carry through but this time, the North Koreans might take him seriously, believe that the US is on the verge of attack, and conclude that the only logical option is to strike first before the Americans take out most of their military assets. Threatening the survival of a weaker country can encourage an itchy trigger finger.

"Well, that doesn't sound good. And I hear we have no good options to stop this. We pass sanctions all the time; they aren't working. A military strike would be a catastrophe. What are we going to do?"

Well, you make an important point. It should be clear by now to everyone that North Korea can build missiles faster than we can impose sanctions that would impede their programme. And a military attack, in the view of most analysts, would risk a full-scale conventional and probably a nuclear conflict of unimaginable devastation.

OPINION: Is North Korea really a 'hollowed out' state?

But there is some good news here. Diplomacy might achieve what sanctions cannot, an immediate freeze on further testing of North Korea's missiles and nuclear devices. The Trump administration has already successfully employed diplomacy with Pyongyang, and the president's own official North Korea policy calls for "engagement" - an approach also favoured by China and US ally South Korea.

To be clear, an agreement that would freeze testing would not mean an end to North Korea's weapons programs, but it will stop them from progressing further at a moment when they are on the verge of developing a nuclear capable intercontinental missile (ICBM). Diplomacy has other advantages as well. History suggests that Pyongyang is better behaved when it's in a negotiation, rather than on the outside looking in. Perhaps most important of all, talks - even if they do not result in an agreement - provide a mechanism for reducing the dangers of misperception and miscalculation.

Another idea worth considering? Stop embarrassing your most important ally. President Trump's impulsive threat of nuclear war on the Korean Peninsula didn't sound like a great idea back in Seoul, not surprisingly. It made the president of South Korea look weak and compelled him to promise in a nationally televised speech that "No one should be allowed to decide on a military action on the Korean Peninsula without South Korean agreement."

And while we're on the subject of the US-South Korea alliance, how about going ahead and appointing a US ambassador to South Korea? This critical position remains vacant despite the obvious risks we face.

"OK. So there are some things we can do. But I want to ask you, as you work on this all the time, what's the big takeaway here?"

For decades, from the 1950s through the 1980s, Americans rightly feared that the existence of nuclear weapons was a pointed gun aimed at their entire civilization - regardless of who owned them. One bad leader, one awful mistake, and the world could face "fire and fury" and the end of the world as we know it.

Then a funny thing happened. The Soviet Union with its thousands of nuclear weapons collapsed, and the biggest threat largely receded - out of mind anyway. The "new" problem wasn't nuclear weapons, it was "proliferation." Proliferation meant their nuclear weapons and those of their friends were fine; it was that those "bad countries" might get nuclear weapons that was the real threat, we were told.

What President Trump's impetuous comments remind us is that all nuclear weapons are dangerous, including our own. An American president - not some rogue dictator - could make a mistake, overreact, or bluff themselves into a nuclear war they did not intend. Leaders, all leaders, are human. To err is human, but to err with nuclear weapons would be catastrophic. Perhaps it is time to take the danger posed by nuclear weapons seriously - all nuclear weapons, even our own.

"OK. Got it. The real danger is nuclear weapons, no matter who has them. But while I've got you here, I was wondering if you could help me with this little problem I have, you see ..."

I'm on vacation in Maine. You're going to have to handle this one.

Jim Walsh is an expert in international security and a senior research associate at the Massachusetts Institute of Technology's Security Studies Program. Walsh's research and writings focus on international security, and in particular, topics involving nuclear weapons.

The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.