30 years ago today, the Labour Party were engaged in an existential struggle against a group of ideologues who were operating within the party, trying to pull it away from electability in pursuit of their political goal. Eventually, in 1985 the Militant Tendency were expelled from the party, but not before their activities had left the party associated with a Marxist stain that probably cost them two more elections. Despite losing those elections, many have argued that winning the battle with the Militant Tendency was Neil Kinnock’s greatest achievement as a leader, and is why the Labour Party exists today.

Today, David Cameron is engaged in what I consider to be a similar existential struggle against a group of ideologues who are putting their political goal above the Conservative party’s long term electability. It is a battle he must win, and he could win by holding the door open for these extremists to leave.

To explain, I will go back to the Militant Tendency, because they story is instructive. They were Marxists, believing in the teachings of Marx, Engels, Trotsky and Lenin. Their policies were classic revolutionary Socialist, and they refused to bend in their insistence that the country to should be run by and for the working class. They engaged in a strategy of “entryism” within the Labour Party, considering that if they could gain a foothold in a major Parliamentary political party they could take it over and pull it in the direction they wanted to go.

As their influence grew in the 70s, they managed to get a motion passed through the 1972 Labour Conference that the 300 biggest companies in the UK should be nationalised ‘with minimal compensation’. They backed the likes of Tony Benn (whom they nicknamed ‘Kerensky’, after the man who was the initial Prime Minister of Russia after the revolution but was quickly supplanted by the Bolsheviks), and managed to get some candidates elected to prominent positions within the Party.

In the early 1980s, as the party tried to deal with Margaret Thatcher’s Conservatives in power, Michael Foot felt he had to proscribe them as a group in the Labour Party as it was felt they were operating entirely separately from it. Foot was a die-hard left-winger himself, but he knew that the Militants’ cry of “No compromise with the electorate” was just not going to work. Neil Kinnock eventually finished this process of when he went into battle against the Militant a Tendency in Liverpool, who had taken over the council, refused to set a sensible balanced budget, then had gone around handing out redundancy notices to employees as a negotiating strategy to get their own budget accepted. It was a hard battle, but Kinnock knew that it had to be won.

Cameron is faced with a similar issue. The extreme right wing of his party have become simply irreconcilable, as evidenced by Matthew Parris’s excellent description of the unwritten “line to take” whenever the Prime Minister makes a speech on the EU or immigration:

“It runs thus: 1 Unless proposals amount to a non-negotiable demand for everything we could dream of plus the kitchen sink, denounce them as “totally inadequate”; “pathetic fig leaf”, “missing the elephant in the room”, etc. 2 If proposals look surprisingly ambitious, denounce as “pie-in-the-sky” and “unachievable” and advise the prime minister to “get real”. 3 If wrong-footed by a favourable public response, denounce Mr Cameron in personal terms as a confidence trickster who won’t keep his word anyway.”

There is a group in the Conservative Party who see themselves as being led far more by Nigel Farage than David Cameron. When Nigel Farage responds to the PM’s measured and sensible speech on Friday, which essentially set out to reduce immigration by reducing the “pull” of our relatively very generous benefits system (particularly our income support system, which allows Firms to underpay staff yet bumps those employees’ pay up way above EU equivalence) Farage said that reducing the pull this country has for immigrants is not the same as controlling it. If that isn’t controlling it, what is? Whipping every immigrant that comes through Dover and Heathrow?

These ‘Irreconcilables’, who number somewhere between 50 and 100 MPs, are muttering about leadership challenges now, and if Cameron doesn’t get a majority in May will almost definitely pull the trigger on that one. But I think that if Cameron loses Downing Street in May he will resign anyway. Before he does that, he has a chance to save the Conservative Party from making itself unelectable in the long term. He needs to tell the Irreconcilables that they should ‘put up or shut up’. He needs to tell them the truth, that he is a Liberal Conservative who sees the long term future of the Conservatives as an electoral force as remaining a party nearer the centre than elsewhere.

The problem for Cameron is that in the short-term, a pact with UKIP might help his electoral chances in 2015. Does he care about the long term future of the Conservative Party, or does he care more about the short term future of David Cameron? I do hope it’s the former.