The rip in the global order may only last four years, but the US chairpeople latest speech leaves European powers with little choice

The Polish army fields three divisions, as does Germanys Bundeswehr. France has two, Romania two, the UK two and the Baltic countries could just about scrape together one. As of last week, those are the only forces Vladimir Putin has to consider as he threatens, bullies and coaxes the countries of the western diplomatic order into disintegration.

Because from the mouth of Donald Trump came only cowardice.

Trump declined to reiterate any commitment to Natos article 5, which mandates reciprocal defence in the face of attack. He lashed Europes leaders about defense spending and then bragged to US troops in Sicily that, as a result of his own election, money is beginning to pour in.

While Theresa May could only smile at her shoes, it fell to a shocked Angela Merkel to spell out what Trump meant. The hours in which we could entirely depend on others are, to a certain extent, over. Ive experienced that in the last few days, she told a party rally. We Europeans genuinely have to take our fate into our own hands.

Behind the scenes, Trumps diplomats signalled it is not just on defence that the multilateral order is under threat. Trump may, as early as this week, pull the US out of the Paris climate treaty. Even if he does not, his commitment to it will be seen as weak. And his aides refused to include a commitment to free trade in the G7 communique.

The true meaning of America first is clear. The Trump presidency will put the interests of American coal, oil and fracking companies first, before that of the planets ecosystem. It will place the interests of US-owned car manufacturers first, above those of Volkswagen and Mercedes. And if it comes to a military face-off with Putins Russia, America will oppose last.

This rip in the global order may last only four years. Or it may snowball.

Either way, it is now rational for both the EU powers and the British government to design a new strategy, for a world where, every very often, the US electoral cycle produces a corrupted, deluded isolationist that we are able to suppose only in monosyllables.

Merkels analysis, if followed to its logical conclusion, must trigger a big change in the economic, trade strategy and security policies of the EU. Her speech should lead Europe to consolidate around its core countries and its core values. If that entails yellow-carding Hungary and Poland, whose infractions of democratic rights are now too large to be ignored, thats fine. Similarly, if the result is a core/ periphery arrangement, with the core becoming a fiscal and monetary union, the sooner the better.

Britain, set on a catastrophic exit from the EUs single market, also faced a wakeup call at last weeks G7. When the UK was the dominant world power, the perfidious Albion tactic attained sense: playing one European power against another and revelling in their weakness. During the post-1 945 epoch of US dominance, perfidious Albion became a no-cost diplomatic reflex, used mainly by British diplomats to get their style in Brussels. This advise to stand aloof from Europe and divide it where possible is hardwired into the UKs diplomatic and geostrategic institutions.

Whatever form Brexit takes economically, it is imperative to unwire it fast. Because Trumps speeches have reshaped the world.

As he shoved minor European legislators in the chest, and tried to crush Emmanuel Macrons hand, Trumps security services were playing equally macho games with photographs of bloodstained dres from the Manchester bombing. The political signal behind that leak was clear: for the Trumpian country, it is the security interest of the US that come first, the priorities of a live anti-terror manhunt in Manchester second.

The xenophobic right in Britain, whose biggest jeerings are set aside for the concept of a European army, had better hope one can be formed. Because after Trumps speech, thats what were going to need to deter the threat of a Ukraine or Crimea situation being created at the EUs borders.

For British politics, this demand for clear thinking comes at the worst possible period. The Conservative cabinet is full of deluded amateurs. People who fantasise about Empire 2.0; people prepared to reimpose a land border on Ireland; prepared to turn the election into a nostalgic re-run of the conflict with the IRA.

Jeremy Corbyn, although he has left behind pacifism and unilateralism, needs to facilitate the emergence of a new, positive Labour defence and security policy. It should be focused on the real threats a disintegrating world order and the growing unpredictability of thousands of jihadis in the UK not just a define of old leftwing nostrums.

The lessons from history are clear. When the US shies away from Europe, as it did between 1939 and 1941, the UK has to function chiefly as a European power, even to seek its own narrow security. As the details emerge of how the Manchester bomber, Salman Abedi, got himself and his bomb to the city, the need for more European cooperation on security will become clear.

In a world as dangerous as this, led by humen as dangerous as Trump and Putin, we should require no prompting to outstrip the 2% of GDP defence spending target, and to reverse all cuts to police, flame and emergency services. The fact is that Trump has signalled that the current strategic concept of Nato, written in 2010, is a dead letter. The major European republics need to craft a new one. And Britain has to be part of that.

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