(CNN) When President Donald Trump delivered his fiery threat against North Korea on Tuesday, many observers mused that he sounded more like North Korean leadership -- that is, bombastic and bellicose -- than any American leader this side of World War II.

But a look back at Trump's past statements on Pyongyang's nuclear program and the Hermit Kingdom's young dictator, Kim Jong Un, shows the President to have been consistently aggressive on the issue, as it relates to US security, over the course of nearly two decades.

Simply put, while the heated language in Trump's remarks to reporters in New Jersey on Tuesday might have been jarring in the moment, no one should have been surprised by the tone.

"North Korea best not make any more threats to the United States," he said. "They will be met with fire and fury like the world has never seen. (Kim) has been very threatening beyond a normal state. And as I said, they will be met with fire, fury, and, frankly, power, the likes of which this world has never seen before."

Reminders of 1999

Trump on Tuesday seemed to recycle some of the language he had used just a few minutes earlier, on the subject of the American opioid crisis, when he said , "We're being very, very strong on our southern border and, I would say, the likes of which this country certainly has never seen that kind of strength."

Like that turn of phrase, Trump's posturing on North Korea has a familiar ring.

During a November 1999 interview with CNN's Wolf Blitzer, the future president warned that, without a diplomatic solution, the US would need to consider military measures.

"You go and you start negotiating," Trump said, "and if you don't stop them ... you will have to take rather drastic actions because if you don't take them now, you're going to be in awfully big trouble in five years from now when they have more missiles than we do.

Asked if that meant he was advocating for a unilateral strike, Trump said, "You can never rule it out."

"That's what they're afraid of," he added. "That's what they're concerned with. You'll most likely with that attitude be able to make a deal. But if you can't, you have to react."

Trump struck a similar note when discussing the issue on NBC's "Meet the Press" that fall. When host Tim Russert asked about the suggestion Trump would, if president, "launch a preemptive strike against North Korea's nuclear capability," Trump first said, "I would negotiate like crazy. And I'd make sure that we tried to get the best deal possible."

Failing that, he ventured, the US should consider preemptive action. (North Korea did not, at that time, have a confirmed nuclear arsenal.)

"You want to do it in five years when they have warheads all over the place, every one of them pointing to New York City, to Washington and every one of our -- is that when you want to do it?," Trump said. "Or do you want to do something now?"

Advice for Obama in 2013

After years of back-and-forth over sanctions, and a broken pledge to give up its program, North Korea in October 2006 claims to have successfully tested its first nuclear weapon. Over the next decade, Pyongyang reported a series of additional detonations, while ramping up its ability to launch an intercontinental ballistic missile -- a development that, in theory, could put the distant US and European cities in its nuclear crosshairs.

By 2013, Kim Jong Un had been in power for more than a year. His father, Kim Jong Il, died of a heart attack in December 2011. Trump has spoken with a mix of qualified admiration, opprobrium and mockery when addressing the young strongman.

"(President Obama) must be very careful with the 28 year old wack job in North Korea," Trump tweeted in April 2013, adding, in a preview of Tuesday's rhetoric, "At some point we may have to get very tough - blatant threats."

Our President must be very careful with the 28 year old wack job in North Korea. At some point we may have to get very tough-blatant threats — Donald J. Trump (@realDonaldTrump) April 6, 2013

Fast forward another three years, and Trump the candidate, in a sit-down with The New York Times , again described nuclear proliferation as the "biggest problem, to me, in the world."

Conflict and confusion on the campaign trail

"You have, probably, North Korea has them. I mean, they don't have delivery yet, but you know, probably, I mean to me, that's a big problem," he said. "And, would I rather have North Korea have them with Japan sitting there having them also? You may very well be better off if that's the case."

Japan, however, has forsworn nuclear weapons and since a little after the end of World War II has been governed under a so-called "pacifist constitution."

When Trump told CNN's Anderson Cooper, days after his Times interview was published, that Japan and South Korea should either protect themselves, with US forces leaving and nuclear weapons taking their place, leaders from both countries expressed disbelief and disappointment

Since taking office, though, Trump has focused more on China when discussing avenues for curtailing North Korea's ambitions. Japanese Prime Minister Shinzo Abe has enjoyed a relatively warm relationship with Trump, including a round of gold course diplomacy during a February visit with Trump in Florida.

JUST WATCHED Trump appears stumped by question on nuclear triad Replay More Videos ... MUST WATCH Trump appears stumped by question on nuclear triad 02:02

Still, Trump's grasp of the nuclear situation, including the extent and particular assets of the American arsenal, is unclear. When asked during a December 2015 primary debate about the US nuclear triad, he gave a rambling answer that suggested he was unfamiliar with the term.

Co-moderator Hugh Hewitt, the conservative radio host, pressed Trump, asking, "Of the three legs of the triad, though, do you have a priority?"

"I think," the candidate responded, "I think, for me, nuclear is just the power, the devastation is very important to me."

(Note: the "triad" is a shorthand for the three means of delivering a nuclear payload , including heavy bombers from the air, in-ground silos holding missiles and submarines with launch capabilities.)

Mutual escalation

Since February of this year, North Korea has launched 18 missiles over the course of 12 tests. The two fired in July, both KN-14, or liquid fueled intercontinental ballistic missiles, have upped the ante -- and tension around the world. On Saturday, the United Nations Security Council unanimously passed a resolution imposing new sanctions on the regime in response.

But even as Trump touted that significant diplomatic coup, a new report, with the potential to completely upend the status quo, was coming down the pike.

It arrived on Tuesday, when The Washington Post first reported that North Korea has "successfully produced a miniaturized nuclear warhead that can fit inside its missiles." Sources have told CNN that, while intelligence analysts now claim Pyongyang is producing the smaller weaponry, it is not believed the capability has been tested.

On Wednesday, Trump's early morning tweets included a claim that his "first order as President was to renovate and modernize our nuclear arsenal." That was false, the order to review US nuclear posture and strategy was his thirteenth

My first order as President was to renovate and modernize our nuclear arsenal. It is now far stronger and more powerful than ever before.... — Donald J. Trump (@realDonaldTrump) August 9, 2017

...Hopefully we will never have to use this power, but there will never be a time that we are not the most powerful nation in the world! — Donald J. Trump (@realDonaldTrump) August 9, 2017

"(The nuclear arsenal) is now far stronger and more powerful than ever before," he added, in a return to the previous day's saber-rattling. "Hopefully we will never have to use this power, but there will never be a time that we are not the most powerful nation in the world!"