What happened to the amiable, hard-working David Frost I once knew?

Frost has finally learnt what decades of Foreign Office experience can never teach – that politics is not diplomacy and there is no loyalty at the top of state power

The David Frost saga should be a warning to anyone who thinks Boris Johnson can be trusted. I first came across Frost when I was Europe minister, negotiating EU enlargement in 2004. He was a middle-rank member of the FCO team, a hard worker, always with his head buried in a computer analysing European Commission texts for his superiors and ultimately for ministers and the prime minister.

Frost’s departure from the cabinet this weekend is a case study in why diplomats and politicians are members of different tribes. After a glittering start as a young FCO official, when he was made private secretary to the permanent under secretary, he fell off the conveyor belt which takes the best and the brightest to the highest ambassadorships – Washington, Paris, the EU and UN, or big embassies around the world. Frost’s highest posting was as ambassador to Denmark, a delightful country but, for an ambitious FCO official, a backwater’s backwater.

He walked out of the FCO twice over his lack of promotion to run the London Chamber of Commerce and then as director of the Scotch Whisky Federation where I met him whenever visiting my son at Edinburgh University.

The Scotch Whisky chieftans believed his diplomatic skills would open markets. Above all, they wanted to penetrate the giant Indian market where Indian politicians imposed a 150 per cent tariff on Scotch to protect their own undrinkable so-called “whisky”. Frost explained to me how, when he led a delegation to Delhi, Indian officials were friendly, served the finest Scottish single malts, and told Frost and the Scotch Whisky Federation they were ready instantly to abolish the 150 per cent tariff on Scotch and allow Teachers or Glenfiddich to go on sale to 1.4 billion Indians.

In exchange, said the Indians, they expected the British government to allow visa-free travel to the UK for a billion or more Indians. Scotch Whisky jaws dropped as they learnt the first lesson of trade deals. They are always political. Frost was never going to get visa-free access to a Britain where a storm of hate was being whipped up against any and all foreigners by the pro-Brexit campaigners headed by one Boris Johnson, along with seasoned anti-Europeans like Chris Heaton-Harris, the former chair of the European Research Group, the Brexit fundamentalists in the Commons.

While Liz Truss will spend her time as foreign secretary seeking to do to Boris Johnson what he did as foreign secretary to Theresa May, new minister of state for Europe Heaton-Harris, a former MEP who knows and loathes all things Brussels, will do the negotiations with Eurocrats.

No one sensed David Frost was anti-European, though he did tell me of his unhappiness with the workings of the European Commission which he felt held back Britain in adopting regulations, and that this did not always benefit British business. I heard the same complaint from every single politician or business leader I met in every EU capital. It was Margaret Thatcher after all who did far more than Tony Blair to transfer sovereign national powers from Whitehall and national ministries everywhere to the commission in order to allow the City and other British firms to trade into  every corner of Europe without let or hindrance.

After the Brexit referendum, when Theresa May took her future political assassin, Boris Johnson, into the heart of government as foreign secretary, Frost told me he was going to work for Johnson as a special adviser. My eyebrows must have visibly raised as he said: “Come on, Denis. Whatever you think of Boris, it is going to be an exciting time for British foreign policy making and it will be fun to be at the centre.”

I had known Johnson since his entry into the Commons in 2001 and was tempted to tell Frost he was not a man to place much trust in. But I kept my counsel. Now in his “Dear Boris” resignation letter Frost writes: “Together we have put this country onto a new path.” He never struck me as a big-headed man but something has changed in the aimable, hard-working FCO official I first met.

Frost was the backroom official faced with one of Europe’s most experienced politicians in Michel Barnier, who had  first held elected office in his twenties and has navigated the treacherous terrain of French centre-right politics ever since. Barnier comprehensively outnegotiated Frost, leaving Britain with a deal that has caused and will keep causing major problems for British firms and citizens for years to come.

Heaton-Harris may hope he can rewrite the treaty Frost negotiated but that won’t happen. He and Liz Truss will soon find themselves the target of the Northern Irish Brexit factionalists, the DUP. They believed Lord Frost was the man who could make Brexit lead to the restoration of a physical border in Ireland, thus abolishing the Good Friday Agreement, which the DUP has described as a “capitulation”.

No British government would deliver the entire nation’s future into the hands of the Dublin-hating, homophobic and anti-women ultras of the DUP. It remains a puzzle why David, now Lord, Frost decided to make himself the DUP ambassador to the EU and try to undo the deal he himself negotiated. Once Joe Biden became president, it was clear that Washington would regard any attack on Dublin and the Good Friday Agreement, which the US sponsors, as a major breach of trust and do enduring damage to the UK’s most important bilateral relationship.

Frost seemed to have forgotten everything he learnt in his FCO years as he tried to appease the DUP. When last week DUP MPs voted with hardline Brexit Tory MPs against Johnson’s modest proposals to increase anti-Covid precautions like mask wearing and Covid passports it was the last straw for Johnson. There would be no more appeasement of the DUP ultras. Their champion in Whitehall, Lord Frost, was told to reverse his line and accept the EU positions on the Northern Ireland protocol.

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Frost finally learnt what decades of Foreign Office experience can never teach – that politics is not diplomacy and there is no loyalty or enduring friendship at the top of state power.

After North Shropshire he could see Johnson’s days are now numbered. Without Johnson, David Frost has no role in government. He is a peer and now promoting the nostrums of libertarian right-wing economics, which won’t work in a country where the state is getting bigger, taxes are rising, and red wall voters are demanding more and more protection. “Levelling up” requires more state, not less. But there will be directorships for the Right Honourable the Lord Frost on offer and for a time applause from the Brexit Europhobes.

Most ambassadors, even those in the highest posts, can only dream of a peerage. Frost would never have got one without selling his soul to the Dr Faustus of Brexit, the current prime minister. Politicians make bad treaty negotiators and diplomats never quite understand the dark arts of politics, particularly the sense of permanent betrayal of close aides that is the hallmark of the current prime minister.

Denis MacShane is a former minister of Europe and author of ‘Brexiternity: The Uncertain Fate of Britain’