During the second world war, Nazi Germany kept expanding its military operations across Europe and into Russia, at every stage oblivious to the possibility that the US might enter the fray.

When Japan attacked Pearl Harbour on December 7, 1941, instead of a frontal assault against Tokyo, President Franklin Roosevelt turned his attention to Germany first, before engaging an “island hopping” strategy to take out Guam, Midway, and Okinawa – then came bombing raids on mainland Japan.

And when Saddam Hussein attacked Kuwait in August, 1990, he also assumed the US would look the other way.

Worst outcome for latest Korean tensions? The status quo

But amassing Iraqi troops on the borders of Saudi Arabia led President George Bush to form the “coalition of the willing” for Operation Desert Storm only a few months later. The goal was to prevent Baghdad from conquering the oil fields of Saudi Arabia and Kuwait in quick succession.

Second, still other US senators could be swayed by the war rhetoric – just how many could determine whether North Korea responds with sudden alarm, or not at all.

However the reactions of senators turn out, either scenario could stir North Korea, and Trump, to action. If North Korea shows indifference and defiance to the US, the latter might feel obliged to send more battle groups to the Korean Peninsula, raising the geopolitical stakes.

If, on the other hand, North Korea acts with alarm, Trump could decide to act decisively to deter Pyongyang from lurching toward any sudden pre-emptive military actions.

Both scenarios are grim, especially if South Korea and Japan begin to mobilise in anticipation of the worst. Already, children living on the west coast of Japan have been told to brace and hide under tables in case of any sudden missile attacks.

Nuclear or conventional deterrence operates on a simple rule of engagement: no side should engage in any behaviour that can precipitate escalation that makes it difficult to stand down from the cusp of war.

By convening the senators, Trump can inadvertently send signals that he is on a war footing – even if in truth it is mere swagger rather than an actual show of belligerent intent. It is a strategy fraught with risks.

Even cold war deterrence between the US and the relatively predictable Soviets had its harrowing moments.

The Pentagon has counted 34 miscues or technical failures that came close to triggering a nuclear weapon during the period, while Eric Schlosser, the author of Command and Control: Nuclear Weapons, the Damascus Accident, and the Illusion of Safety cited “more than a thousand” such events from documents released by the US National Security Archives.

In one incident in the 1980s, a Soviet radar officer, Stanislav Petrov, suddenly saw an incoming array of missiles on his monitor crossing Russian airspace.

“The siren howled, but I just sat there for a few seconds, staring at the big, backlit, red screen with the word ‘launch’ on it,” he said.

The system was telling him that the level of reliability of that alert was “highest”. There could be no doubt. America had launched a missile.

“A minute later the siren went off again. The second missile was launched. Then the third, and the fourth, and the fifth. Computers changed their alerts from ‘launch’ to ‘missile strike’,” Petrov told the BBC.

Will China stand aside if North Korea wants to talk to Trump?

Before pressing the button for a retaliatory strike, as he was trained to do, he hesitated for a moment and guessed it was a computer glitch – his hunch perhaps saved the world from nuclear oblivion.

While the Soviet radar officer guessed right, Trump, Kim or those working on their behalf could easily guess wrong, triggering an accidental and devastating war. Fearing this, China is warning the US of the risks based on it’s own war experience with the Soviet Union.

In 1967, China assumed that the Soviet Union was about to cross the Ussuri River in Northeast China to conquer China. Moscow had no such desire. But this event spooked Chairman Mao Zedong (毛澤東) and he rallied his people for nuclear war. Many Chinese remember this incident more vividly than many in the US recollect the Cuban missile crisis, and most of the US remains oblivious to how close China came to the brink of nuclear war – the world could suffer tremendously if the US doesn’t learn from the lessons of the past.

Christopher Hill, the dean of the Korbel School of International Relations at the University of Denver, affirmed that there are “at least 20 million Koreans alone who live in the artillery range of North Korea”. This should make the US think twice before poking a stick in the eye of Kim Jong-un.