How do you succeed in politics? To paraphrase US General Norman Schwarzkopf, have a good plan and execute it violently. Do not be like the Coalition and have a confused plan which you implement incompetently. The catastrophic collapse in polling support – not just two-party preferred but the Prime Minister's personal ratings – was made entirely in Canberra. It is worth reflecting on why it has all gone so badly wrong.



The first thing to understand is that the heart of the budget strategy is a very simple argument: "Labor made a mess of the budget. We'll clean it up. There will be hard decisions. If you don't like them, blame Labor." This is pure political plagiarism. Tony Abbott and Joe Hockey have tried to copy the playbook of British Conservatives David Cameron and George Osborne, who have successfully convinced voters that British Labour are responsible for the GFC and all its fiscal and economic consequences. The problem for the Coalition is not the broad strategy – it can, as British Tories have shown, be effective. The thing is that, as a blunt argument, it requires a subtlety of execution. This has been completely lacking.



Firstly, take the messaging. This needs to be absolutely consistent. It is a political cliche that it is only when you are sick of repeating something that the public are starting to hear it. But like most cliches, it is true. There is, finally, a crisp clarity about Abbott's sound-bite that he's dealing with "Labor's debt and deficit and disaster" – a phrase no doubt tested to death in focus groups. But this attack line is coming late in the day – the week after the budget when it should have been the drumbeat for the preceding months.



Secondly, messaging is only as good as the underlying argument. And to be honest, the government just isn't sure what its argument is. The best question to ask any politician making a self-avowed hard choice is: "Are you doing this because you want to, or because you have to?" It is surprising how confounding that query can be. The intention of the Coalition strategy was to say they had been forced to make cuts by Labor's incompetence. Or, as we say in Scotland, a big boy did it and he ran away. The trouble is Joe Hockey muddied his argument with his National Commission of Audit. At the time it was established, it seemed to have an obvious purpose – to make the case for the prosecution. From that point of view, its menu of cuts works – it makes the voters' flesh creep. Hockey's error, though, was to adopt too many of the ideas. Two painful emblematic cuts would have said "Blame Labor". Adopting so many of the ideas is ideological and admits, effectively, "I want to do this". Which also means "Actually it's not Labor's fault".



That's why so much of the messaging is incoherent. Take the co-payment for GPs. Is it a gentle nudge? A frictional payment to make patients think twice before using a GP? Is it a budget necessity? Or is it the right way to fund medical research? It can't be all of these – they are mutually contradictory. Yet each line has been trotted out.



Thirdly, don't fight on too many fronts at once. Political conflict defines, for sure. But only take on the battles that you need to take on, and fight them on your own terms and in your own time. Look again at David Cameron. He quarantined spending on health, education and foreign aid. Loading cuts on to welfare, bureaucrats and local councils – victims with few friends. In contrast, Abbott and Hockey have a stoush with the states about hospital cuts which starts in July. They have a fight with states and the voters to win an argument that spending on sustainable health and education requires expansion of the GST. At the same time, bringing in the highest state pension age in the world is terrifying suburban voters. And GPs are up in arms. They worry about the extra staff and security they need if they have to handle cash. Already they have patients phoning up to find out if they have to pay $7 a visit. The way this is being handled by doctors should terrify Abbott. A friend of mine was waiting to see her GP this week and overheard the receptionist reassuring a patient that the payment wasn't in force yet, and that anyway "the Labor Party were trying to stop it". What an endorsement for Bill Shorten and from one of the most trusted sources in the community.



In the end, government is hard, really hard. It finds politicians out. This is not to say that opposition is a walk across an open field, but tight control and a firm direction are easier. Particularly because shadow cabinet colleagues, backbenchers and party powerbrokers will bury differences beneath a poll lead. In the end, the difference is that an opposition leader wakes every morning wondering about what to say and whether it will be heard, while a prime minister wakes thinking about what to do. To win you need a strategy and that doesn't simply mean setting out what you want to do. It means gaming what the reactions will be, anticipating them and neutralising them. The budget presentation has been the ultimate lesson in how not to do things.

John McTernan is a British Labour Party political adviser, strategist and commentator. He was director of communications for Julia Gillard from September 2011 to June 2013.