Prior to US president Donald Trump’s speech before the United Nations General Assembly on 19 September, no UN member had ever openly stated its intention to destroy another country.

Coupled with his earlier threat to rain “fire and fury” on North Korea, this threat includes the possibility of a nuclear attack.

It is true that Trump’s threat was conditional on North Korea threatening the US or its allies. But he left vague what that means. He has stated repeatedly that the US would not tolerate a nuclear-armed North Korea with the ability to deliver a weapon to the United States.

North Korea is already nuclear armed. Its recent missile tests demonstrate that it is well on its way to be able to hit the US, and it already has the capacity to hit Guam. North Korea says that it will continue its nuclear and missile program unless the United States finally puts an end to the Korean War by signing a peace treaty with the North.

No US politician, from Bernie Sanders on the left to the most extreme rightist Republican (take your pick), is ready to do anything that even moves in that direction. On the contrary, with bipartisan support, the US just completed its annual belligerent “war games” in South Korea, the aim of which is to threaten the North. These “games” include the South’s army, but that army is under the command of the US.

South Korea’s new president, Moon Jai-in, was elected on the promise of seeking dialogue with the North and restricting the deployment of the US Thaad anti-missile system. But Trump bullied Moon into reversing his positions. Now the South is deploying a special commando unit with the avowed public goal of assassinating the North’s leadership.

One purpose of Trump’s threat to destroy North Korea is to force China to stop supplying oil to the country, which would devastate its economy, in the hopes that this would force the regime to abandon its nuclear program. In all likelihood, this will not come to pass.

China does not want the North to collapse, which it would under an oil embargo of any length of time. That would lead to a US invasion resulting in a united Korea as a militarised client state of the US on China’s border. Even if Chinese president Xi Jinping grovelled before Trump and cut off the oil, a desperate North, facing collapse, would likely strike back.

When president Franklin Roosevelt imposed an oil embargo on Japan as part of the intensifying rivalry between the two powers in the 1940s, Japan replied by striking at the US naval base at Pearl Harbor, Hawaii, triggering the Pacific War.

It is obvious that the increasing tensions between North Korea and the US pose a very serious danger, and Trump has just upped the ante with his UN speech.

North Korea has solid reasons for fearing a US attack, given Washington’s hostility going back to the end of the Second World War. After the defeat of Japan, which had been the colonial power in Korea, the US tried to occupy the whole Korean peninsula. However, it was able to take only the southern part because the USSR occupied the north.

What became South Korea was ruled by the US military directly from 1945 to 1948. Meanwhile, the Soviet Union withdrew its armed forces from the North. In 1948, Washington’s military staged phoney elections in the South, installing the first in a long line of dictators.

At the end of the war, the US also tried to occupy parts of China, much of which had been occupied by Japan. China was the big prize the US coveted. However, this plan had to be scrapped because of a mass uprising in the US armed forces, called the “bring us home” movement, which baulked at invading what was viewed as a US ally. The US had influence with the government run by the Nationalists.

Then, in 1949, the Chinese Revolution completely tore the country out of the US imperialists’ hands. China now became Washington’s enemy. The US, using hostilities between North and South Korea as a pretext, invaded Korea in 1950 and quickly moved deep into the North, threatening to continue into China. China countered by sending its army into Korea, blocking the US advance.

At that point, president Truman considered using atomic weapons against the Chinese and North Koreans. Nine nuclear bombs were transferred to the US-occupied Japanese island of Okinawa, along with bombers to deliver them. Fortunately, Washington decided against using them, which would have meant a major war with China and the Soviet Union.

The war continued until 1953, when a ceasefire recognised that it had become a stalemate. The North and South were again divided along basically the same lines as before the US invaded. An armistice was signed, but not a peace treaty. The US and its puppet regime in the South remain in a state of war with the North.

China withdrew its troops from the North, but the US has maintained its occupation force in the South up to the present.

In 1958, the US stationed tactical and strategic nuclear weapons in the South, aimed at the North, which would also be used against China and the Soviet Union in the case of a general nuclear war. At its height, there were 950 US nuclear warheads in South Korea. The US weapons were removed in 1991 as part of the Strategic Arms Reduction Treaty. The US threat against the North then resided in the atomic weapons in the US naval fleet in the western Pacific, as well as other parts of Washington’s nuclear arsenal.

Beside the enormous inequality between small North Korea and the heavily armed US, there is the gross hypocrisy of Washington. The US was the first country to develop atomic weapons, and tried at first to keep a monopoly on them. That began the nuclear arms race.

The US is the only country to have unleashed atomic weapons against civilians, in the bombings of Hiroshima and Nagasaki. The purpose of those bombings had nothing to do with Japan, which had already been defeated, but to demonstrate that the US had the inhumanity and the will to repeat such bombings of cities, first as a threat against the Soviet Union before the latter developed its own nuclear weapons, then also against China, which did likewise, but also against any potential enemy of the US.

The US has never renounced the first use of nuclear weapons, and is opposed to any possible treaty to abolish such weapons.