Hong Kong (CNN) In the dog days of 2017, when it appeared North Korea and the United States were on the path to war, a debate raged in the halls of the White House .

If the US military conducted a limited series of strikes on North Korea, would it scare Kim Jong Un enough to stop the young leader's dogged pursuit for nuclear weapons and ballistic missiles?

North Korea's answer, at least in state media, was a resounding no. Pyongyang warned it would respond to any military action against its sovereign territory with force of its own.

"The empire of America would go to the hell and the short history of the US would end forever, the moment he destroys even a single blade of grass on this land," a commentary in state media said in February 2018, months before Trump and Kim's first meeting.

We'll never know whether North Korea was serious.

In the end, President Donald Trump never ordered a strike, thanks in large part to the diplomatic efforts that led to Kim and Trump's historic meeting in Singapore in 2018.

But behind North Korea's colorful threats was always an important message: Pyongyang is developing nuclear weapons and ballistic missiles capable of reaching the US, so decision makers in Washington will think twice about whether to conduct a so-called "bloody nose" strike or, say, kill a general whom is deemed a terrorist and an imminent threat.

This is likely the lens through which North Korea views the Trump administration's decision to kill Iranian commander Qasem Soleimani in a drone strike on Friday , a strike that has thrown the Middle East into crisis and inflamed tensions between Tehran and Washington even further. Washington didn't have to fear nuclear retaliation with Iran. But it does with North Korea.

"North Korea is right next to Iran on the state sponsor of terror list. And the administration is now justifying the assassination of Soleimani by calling him a terrorist," said Adam Mount, a senior fellow at the Federation for American Scientists.

Soleimani's killing, Mount said, would likely strengthen North Korea's resolve to expand its nuclear deterrent.

"In case something happens to their leadership, they can credibly threaten to impose costs," he said.

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From 'Axis of Evil' to 'Fire and Fury'

When President George W. Bush entered the halls of Congress to deliver his first State of the Union speech after the 9/11 attacks, few -- if any -- on the Korean Peninsula knew that the Kim Jong Il regime was about to be included among the infamous "Axis of Evil" trio.

The ensuing decision to include North Korea along with Iran and Iraq, and the subsequent invasion and overthrowing of Saddam Hussein, likely helped convince Kim's regime that it needed nuclear weapons to ensure its survival.

Pyongyang has pointed to leaders like Hussein and Moammar Gadhafi of Libya as telling examples of why it needs nuclear weapons, and why it is so hesitant to give them up in negotiations. Gadhafi agreed to abandon his nuclear ambitions in exchange for sanctions relief in the early 2000s. Within years, he was overthrown and killed by rebels backed by Washington.

"North Korea already believed the US couldn't be trusted. It already believed its nuclear weapons were the only thing that made its fate different than Iraq or Libya," Van Jackson, a former official in the Defense Department under the Obama administration, told CNN.

Trump has hoped that a top-down approach to nuclear negotiations could help him succeed where his predecessors had failed. But the diplomatic negotiations between Washington and Pyongyang that have followed the three summits between Trump and Kim have not made any progress in part due to the issue of trust -- or lack thereof.

Kim Jong Un walks with Donald Trump at the DMZ dividing the Koreas on June 30, 2019.

Both sides have accused the other of being inflexible in their attempts to reach a deal that would see Pyongyang trade its nuclear weapons and ballistic missiles in exchange for relief from the economic sanctions that have crippled the North Korean economy.

Kim was quoted as saying his country "will never" give up its nuclear weapons if the US "persists in its hostile policy" in an important speech published New Year's Day.

"The US labeled our state as its enemy, 'axis of evil' and target of its 'preemptive nuclear strike' and applied the most brutal and inhuman sanctions against and posed the persistent nuclear threat to the latter over the past seven decades," Kim was quoted as saying in a speech.

The issue boils down to a catch-22 that has eluded diplomats for years.

North Korea would probably only get rid of its nuclear weapons program if it had a trusting and stable relationship with the United States. And the US would likely only develop a normal relationship with North Korea, remove sanctions and help Pyongyang grow its economy if it abandoned its nuclear weapons program.

But the decision to kill Soleimani has added another wrinkle. It proves Trump's threats are not always bluster, which could give North Korea reason for pause if it was considering doing something provocative, like testing a long-range ballistic missile or nuclear weapon.

It could also be more dangerous. If Kim believes Trump would order a drone strike on North Korea, "then he may feel greater pressure to keep his nukes on a hair trigger," Jackson said.

"There are a lot of questions about North Korean nukes that we don't have answers to, and until we do, it's crucial that we don't make foreign policy decisions that introduce greater risks of nuclear instability."

Correction: This story has been updated to better reflect the conditions in which North Korea could end its nuclear program