Whoa! There he goes again. Donald Trump’s impulsive decision to rubbish a landmark arms control treaty and develop a new generation of American nuclear weapons deals another devastating, dangerous blow to the rules-based global order. It seems Trump only has to look at an international treaty or a multilateral institution, and he is overcome by an irresistible urge to tear it down.

The man is a menace, that much is true. This latest piece of wilful vandalism will put everyone at greater risk. It’s terrible news for all who seek a nuclear-free world. It’s a significant backwards step away from the obligation of all declared nuclear weapons states, under the 1970 nonproliferation treaty, to reduce and eliminate their arsenals. It’s a reckless, irresponsible act.

But that’s not the worst of it. Trump’s decision, if implemented, fires a starting gun in a second-phase global arms race that could be even more frightening than the two-sided superpower contest that halted when the Soviet Union imploded. The world has changed since 1991. This time around, the race could be many dimensional and multipolar, making it harder to contain. This time, the threat of mutual annihilation will be replaced by multilateral assured destruction.

Trump’s double standard also extends to Iran – ironically, the only country that has kept its nuclear word

It’s possible Trump’s announcement could be a ploy, intended to pressure the Russians in a week when John Bolton, his national security adviser, is holding talks in Moscow. It would be typical of this president to threaten Armageddon only to make nice later, as he did with North Korea. Trouble is, Vladimir Putin is no weak, marginalised actor, like Kim Jong-un. The Kremlin has vowed to match new US weapons, warhead for warhead.

Specifically, Trump justifies his decision by saying Russia’s deployment of new, mobile, medium-range, land-based, nuclear-capable cruise missiles breaches the 1987 intermediate-range nuclear forces (INF) treaty. It’s not a new problem; Barack Obama wrestled with it. And the west knows, to its cost, that Putin is in offensive mode on a range of fronts. In March, he ostentatiously displayed Russia’s modernised arms chest, unveiling a 15-warhead long-range missile, wizard underwater drones and a hypersonic missile called the “dagger” that could, he said, strike like a meteorite.

Such juvenile bragging aside, Russia maintains – with some justice – that it is the Americans who have undermined the INF pact by spending billions of dollars on upgrading existing nuclear weapons systems and making them more “usable” by lowering their explosive yields. Fundamentally threatening, from Moscow’s perspective, was George W Bush’s unilateral decision in 2002 to quit the 30-year-old anti-ballistic missile (ABM) treaty, another cold war arms-control building block. Russia says the subsequent US deployment of antimissile defences – the current Nato-run “missile shield” is based in Poland and Romania – tipped the European balance of forces against Moscow.

Trump’s INF decision also reflects American concern, shared by the Russians, about China – which is not bound by the agreement, and is developing medium-range systems. A possible future threat to Russia’s far east is another reason why Putin believes he needs the mobile, land-launched missiles. Given rising military confrontation between American, Chinese and other nations’ forces in the South China Sea, and Beijing’s aggressive stance towards Taiwan, it is not hard to see why generals on all sides, mired in old, cold-war thinking, take a similar view.

Minor-league nuclear-armed states, such as the UK and France, cannot escape a share of blame for this across-the-board deterioration in nuclear security. London and Paris can barely afford their nukes, financially or morally. They are less an “independent deterrent”, more a forlorn symbol of forfeited great power status. Both governments should set an example to unmonitored nuclear states such as Israel, Pakistan and India, and others who may in future seek to “go nuclear”, by unilaterally disarming. But even Jeremy Corbyn, a lifelong anti-nuclear campaigner, cannot bring himself to promise that, lest it derail his political ambitions.

All of which brings us back to Trump, and the breathtaking hypocrisy of a man who last year threatened to “completely destroy” North Korea because it had the temerity to build atomic bombs. Trump insists Kim must disarm totally – even as he plans to expand the US nuclear arsenal. Has the White House considered how this may affect Pyongyang’s willingness to talk peace?

Trump’s double standard also extends to Iran – ironically, the only country that has kept its nuclear word. Tehran faces extreme US sanctions despite its scrupulous adherence to the multilateral 2015 nuclear deal that Trump jettisoned earlier this year. Iran’s leaders will look at this latest exercise in treaty-busting and say America, once again, has shown that its solemn word cannot be trusted. Hardliners will argue it proves the case for an Iranian bomb.

If Trump goes ahead, and the Kremlin responds in kind, it could mean the return to Europe after 30 years of US land-based missiles, dread offspring of the cruise and Pershing missiles whose deployment in the 1980s was resisted by CND and the Greenham Common women’s peace camp. Alternatively, there could be major new deployments of US air- and sea-launched missiles, plus renewed pressure on Nato countries to put more cash in the kitty.

The trashing of the INF treaty could also kill off an arguably even more important pact, the New Start strategic weapons reduction treaty, negotiated by Obama in 2010, whose renewal in 2021 is already far from certain. In short, the knock-on effects of Trump’s act of gross irresponsibility are globally destabilising, unpredictable and wildly risky. They point to a world for ever ruled by fear of nuclear destruction. But then, fear is how Trump works.

• Simon Tisdall is a foreign affairs commentator. He has been a foreign leader writer, foreign editor and US editor for the Guardian