Johnson’s imperial bombast could suck Britain into more deadly interventions

Relations between the world’s great powers are tenser than ever since the cold war. Troops are massing along Russia’s border with Ukraine. Chinese ships and planes are openly threatening Taiwan. Japan is rearming in response. Turkey is renewing its belligerence towards its neighbours. Russia is backing east-west fragmentation in Bosnia.

Where Britain stands in all this is dangerously unclear, drifting on a sea of Boris Johnson’s gestures and platitudes. The Royal Navy currently has a £3.2bn aircraft carrier waving the union flag in the South China Sea, completely unprotected. China could sink it in an hour. In the Black Sea, a British destroyer provocatively invades Russian waters off Crimea, showing off to the world’s media. Last week, the British foreign secretary, Liz Truss, advanced her bid for her party’s leadership by sitting astride a tank in Estonia and warning Russia that Britain “stood firm” against its “malign activity” in Ukraine. Meanwhile, Britain’s outgoing defence chief, Sir Nick Carter, estimates that the risk of accidental war with Russia is now “the highest in decades”.

There is no evidence of a coherent strategy in these moves. Johnson is travelling a familiar path, seeking foreign glory to distract from domestic woes. He has announced a reversal of Britain’s 1960s withdrawal from “east of Suez”. He seeks something called an “Indo-Pacific tilt”, and a projection of what he calls “British leadership in the world”. His March defence review proposed a 40% increase in Britain’s nuclear stockpile, in flagrant defiance of the 1968 nuclear non-proliferation treaty. To push home the point, he appointed the navy’s expansionist Admiral Tony Radakin as his new chief of defence staff, reportedly against military advice.

What this has to do with Britain’s defence is obscure. None of it falls within any treaty obligation. London has no obligation to get involved in China’s argument with Taiwan, nor does Taiwan even want it. Yet when Theresa May last month asked Johnson if his anti-Chinese Aukus treaty with Australia and America committed Britain to military action, Johnson played macho and refused to answer.

Nor has Britain any obligation to defend Ukraine, which is not a member of Nato. Yet Truss appears to suggest otherwise. As for Iran, Brexit ended Britain’s need to impose crippling – and useless – economic sanctions. Yet it continues with them, even using them to refuse to ransom the imprisoned Nazanin Zaghari-Ratcliffe. Most extraordinary, Johnson appears personally to have rescinded a pledge that Britain would never be the first to use a nuclear weapon in any future conflict. What conceivable credibility can be attached to such a threat?

None of these bellicose emanations from the prime minister has anything to do with British security. They are play-acting. Britain is at liberty to say what it thinks about the authoritarian regimes in Russia and China – indeed it has a moral duty to do so, as it has to accept refugees and extend aid to the needy. Such duties have nothing to do with defence. Yet Johnson’s ambiguous words and actions carry implications. Casual promises to confront and act, not stand idly by, can be misread and lead to no less casual commitments to deploy violence.

Related: US warns Russia has plans for ‘large scale’ attack on Ukraine

Just such a morass of bombastic threats and counter-threats were hurled into the fury of instabilities that preceded the first world war. It was a similar bout of sabre-rattling that led the great powers to the nuclear cliff-edge during the Cuban crisis of 1962, and the Andropov miscalculation of 1983. Recent analyses of both have shown how truly close was disaster, saved only by the luck of having sane leaders at the time. There is no such guarantee today.

We can all see that the world faces dictatorships in Beijing and Moscow. Both are flexing their muscles internally and doing externally what both Britain and America did in their imperial prime, which is expand their influence. They see the west’s global confidence dwindling. Democracy is sick, with America in turmoil and Europe dis-uniting. Neither Russia not China actually threatens the west, but both want to strengthen their spheres of control over their neighbours as powerful states have always done. China’s “belt and road” strategy is a reprise of Britain’s imperial preference.

If any lesson is to be learned from recent decades, it is that the western powers are ill-advised to meddle in the power structures of China, India and the Middle East. They are not good policemen. They should accept that their role is to exemplify their much-vaunted western values at home, not force them on other nations and cultures in the manner of medieval crusaders. This merely condemns them to humiliation and their victims to the devastations of groups such as Islamic State and the Taliban.

At this moment the world most needs wise and calm statesmanship. On leaving Afghanistan, Joe Biden at least had the dignity to learn the obvious lesson. It was over. Withdrawal should mark “the end of an era of major military operations to remake other countries”, as Biden put it. Other countries should be left to their own devices.

No such lesson has come from Britain. All Johnson can do is boast that he is the ruler of a “global Britain”, and spend a fortune on useless weaponry. Can we imagine a German or French leader indulging in such imperialist bombast? In doing so he risks sucking his country into yet more murderous interventions. They can have nothing to do with his nation’s security. They are political vanity.

• Simon Jenkins is a Guardian columnist