Over the past few days, the United States and North Korea have become locked in nuclear brinkmanship. After North Korea declared that its ballistic missiles could hit anywhere in the United States, President Trump vowed that continued North Korean provocations would be “met with fire and fury and — frankly — power.” North Korea responded by threatening to attack the tiny island of Guam, a U.S. territory.

But it was another tiny island that set the United States and North Korea down this path. Few Americans will recall the 1983 invasion of a small Caribbean nation thousands of miles from North Korea. But in fact, this conflict set the stage for the nuclear standoff today. It intensified the animosity between the two countries, sending North Korea on a quest for nuclear weapons to combat what it saw as a looming U.S. threat.

In October 1983, the United States invaded Grenada. The Kim family regime that controls North Korea saw this invasion as an early warning sign: If the United States could perceive even a small spice island as a threat, so too could it eventually train its sights on North Korea. Without an effective deterrent, any regime perceived as a threat would be little match for American military might.

Don’t give Trump too much credit for disrupting international relations on North Korea. (Adriana Usero, Kate Woodsome/The Washington Post)

It wasn’t just Grenada’s size that caught the Kim family’s attention. Grenada, a country of only 110,000 people that is known primarily for producing nutmeg, had significance for the North Korean leadership in the late 1970s and early 1980s. Kim Il Sung, grandfather of North Korea’s present-day leader, Kim Jong Un, viewed the new Grenadian socialist government headed by Maurice Bishop as brave revolutionaries directly fighting U.S. imperialism in the Caribbean. Kim Il Sung also sought the help of recently decolonized nations like Grenada in international forums, as a way to undermine South Korea’s legitimacy abroad and garner support for a North Korean-led reunification of the two Koreas.

Shortly after establishing diplomatic relations with Grenada in 1979, Kim Il Sung offered large amounts of free technical and agricultural assistance to Bishop’s regime. From sending tractors and cement to helping build the national stadium in the capital city of St. George’s, North Korea spared no expense in assisting its Grenadian allies.

The North Koreans also provided a large cache of weapons to Grenada. According to documents captured by American military forces during the invasion, when Bishop visited North Korea in April 1983, the two countries signed a secret military agreement. North Korea’s “free offer of military assistance” gave the Grenadians $12 million worth of weapons and ammunition, which included 1,000 automatic rifles, 30 heavy machine guns and 50 rocket-propelled grenade launchers. Richard Jacobs, Grenada’s ambassador to the Soviet Union, remarked at the time of the U.S. invasion, “We have the best Soviet, Czech and North Korean military equipment; we will win the fight, no question about it.”

President Ronald Reagan justified his decision to launch Operation Urgent Fury by citing the presence of 600 American medical students in Grenada and a military coup that took place six days before the invasion. Reagan argued that the coup, which deposed Bishop and brought even more radical Stalinists to power on the island, threatened to destabilize the entire Caribbean region.

The North Korean news media attributed far darker motives to the United States. A Nov. 6, 1983, article titled “The U.S. Imperialists’ Invading Army Carries Out Brutal Crimes Against Humanity in Grenada” described American “atrocities” and “slaughter of peaceful residents,” such as the bombing of a hospital and the firing of missiles at residential areas, including near a kindergarten. North Korean propagandists depicted this conflict as David vs. Goliath, with the Grenadian Davids bravely resisting a mighty invading army.

Despite the generous provision of free weapons by North Korea, the Grenadian military forces soon succumbed to the better-trained, more experienced U.S. forces, which toppled the socialist government in December 1983.

The North Korean government continued to blast the U.S. invasion long after Operation Urgent Fury ended, a sign of the lasting impact that it had on Kim Il Sung and his advisers. In 1984, elections were held in Grenada, which the North Korean media branded “political humbuggery stage-managed by the United States.” A year later, the North Korean media labeled the new Grenadian government a U.S. puppet.

After observing the swift destruction of the Grenadian revolution, Kim Il Sung feared that Reagan would launch an invasion of North Korea similar to Operation Urgent Fury and overthrow his government in a matter of weeks. Reagan’s strict anti-communist policy and his increased commitment to the U.S.-South Korea military alliance — Reagan had ratcheted up joint military exercises on the peninsula — unsettled Kim Il Sung.

In a 1984 conversation with East German leader Erich Honecker, Kim Il Sung lamented, “Every year the American armies conduct a major military exercise. They conducted these exercises even before the Reagan era, but since Reagan took office this has grown.” Kim Il Sung also fretted to Honecker that Reagan would never withdraw U.S. troops from South Korea and that the American military presence would impede his plans for the reunification of the Korean peninsula. Kim Il Sung perceived Reagan’s combination of staunch support for South Korea and militant rhetoric, on top of the invasion of Grenada, as a sign that North Korea might be next.

He knew that just as Grenada’s military could not match the powerful United States military in battle, neither could his military stop a U.S. invasion. He knew that he needed a far greater deterrent to keep the Americans at bay and protect his regime. Thus, three years after the U.S. invasion of Grenada, the North Korean leadership established a Ministry of Atomic Energy Industry, which formally declared Kim Il Sung’s intention to develop a nuclear weapons program.

The North Korean media still regularly refers to the “illegal” invasion of Grenada as evidence of Washington’s ambitions to dominate the world. This event, and others like it, influence how North Korea negotiates with the United States.

North Korea will never abandon its nuclear weapons program, because it believes that without it, nothing would deter an American invasion aimed at regime change. North Korea will not even establish a dialogue with the United States if the Trump administration insists on Kim Jong Un dropping his nuclear weapons program.

This posture leaves the Trump administration with two poor options. One option: deal with the reality of a nuclear North Korea, which is unacceptable given Kim Jong Un’s unpredictability and Pyongyang’s militant ambitions to reunify Korea. The other option — really, the only realistic option — is to pursue an even more active and stringent secondary sanctions policy, which has yet to be tried due to the fear of Chinese reprisal, and to continue to strengthen the U. S.-South Korean military alliance that has made peace possible on the Korean peninsula since the signing of the Korean Armistice Agreement.

The Trump administration now confronts a complicated situation that could quickly unravel into a devastating war. To begin to counter that threat, the United States must assure its allies in East Asia, South Korea and Japan that Washington will honor its military commitments. But the United States must also reassure the wider world community that it will not be the aggressor, as it was in Grenada more than 30 years ago.