Brexit didn’t just happen even though the British were increasingly aggrieved at the thousands slipping across from Europe to claim social security and medical benefits in the UK.

Brexit was a war fought on many fronts by British parliamentarians, most ruthlessly by those within David Cameron’s own Conservatives.

Westminster journalist Tim Shipman, Sunday Times political editor and a key force behind the Times’ whimsical Red Box daily email politics briefing, has published an account of the conflict; All Out War – the full story of how Brexit sank Britain’s political class a meticulously detailed account of the campaign written by an insider who spoke the language of upper-class Tories. It reveals why, and how, Cameron had to go, after the referendum that he should not have embarked on, and having done so, floundered, unable to stare down his German adversary, ideology-driven ‘Mutti’ Merkel, who after 32 years of restricted life in East Germany, was determined to hold Britain to the EU’s ‘open borders’ policy .

For Australians, Shipman’s book is a warning; this is how the game is played when the stakes are high enough, voters sufficiently pissed off and the Europeans, led by Merkel, uncompromising on the EU’s core tenet of ‘freedom to cross borders’.

Ironically, Cameron, Shipman notes, was not an EU enthusiast, his views, ‘no to the single currency, no to further transfer of powers from Westminster to Brussels and yes to areas like fish, where the EU has been a disaster for the UK’ were well known to his party.

It was immigration that swung the referendum, the huge cost of migrant benefits borne by British taxpayers, and Merkel’s announcement –incomprehensible to many Tories – that refugees in any number of them were welcome in Germany.

Teresa May, then one of Cameron’s quieter Conservatives, wrote a newspaper article that said migrants should be banned from entering Britain unless they had a job there and called on EU leaders to abolish freedom of movement and questioned the Schengen Agreement, which underwrote the policy, saying it led to deaths at sea and people smuggling.

The Conservatives who were to end David Cameron’s leadership went to work, the special advisers, Party donors, fundraisers, and those who, like Nigel Farage, Michael Gove and Boris Johnson, kicked along the idea that Britain could go it alone.

The ‘Out’ campaign was born. An online video posted told viewers ‘Every week the United Kingdom sends £350 million of taxpayers; money to the EU. That’s the cost of a fully staffed, brand-new hospital, or looked at another way, that £20 billion per year…. Vote Leave, let’s take control.’ The message came from a rented office with ‘temporary carpet… with wires still hanging out’, Shipman wrote.

As the ‘Leave/Remain’ campaign rolled along, few outsiders were recruited to power the argument. An exception was POTUS, Barack Obama, who, unluckily for the ‘Stronger-Ins’, unwisely delivered his veiled ‘back of the queue’ warning to British voters against leaving the EU at a joint press conference with Cameron held at the Foreign Office.

Reaction from focus groups was immediate and angry in Britain (as it would be in Australia) ‘How dare the president of the US say that to Britain when we’d been first in the queue when it came to military action in Iraq and Afghanistan? We’ve got a special relationship with the US, do how dare the president of the US come over here and insult us like that and intervene in our referendum ?’ That backfired.

Ironically, the by-now-besieged Remainers were counting on Jeremy Corbyn — ambivalent at best on the EU — to help them win back the ground that the Leavers and Ukip, bolstered by several defecting Tories, were steadily gaining. Instead, Corbyn said Labour would back the EU ‘warts and all’.

When it was all over – David Cameron sitting silent in the Thatcher Room at Number 10 as the results came in, his little girl Nancy asleep at his feet – leading Brexiteer Tory Daniel Hannan jumped on a desk and delivered a version of the Agincourt speech from Henry V “From now on every year it comes round, you guys will be remembered. Our names will be familiar in their mouths and household words – Duncan Smith and Penny Mordaunt and Dominic and Oliver and Douglas Carswell and Parky and Starky … every year this will be our day.’

For the underdogs had prevailed.

All Out War: the full story of how Brexit Sank Britain’s Political Class by Tim Shipman is published by William Collins

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