Well, that went well. Kwasi Kwarteng’s decision to axe the 45 per cent top rate of income tax triggered a crash on the financial markets. It then ran into so much opposition from the public and from Conservative MPs fearful for their seats that it had to be scrapped completely. Right now, it seems unlikely that any politician will want to revisit the subject any time in the next two or three millennia. Abolishing Christmas would be less toxic. If they do, however, one point is surely clear: the 45 per cent rate is here to stay. The only way any politician will ever be able to scrap it now is by stealth.

For all the hullabaloo around the 45 per cent top rate of tax, it makes little sense for the economy. The tax only raised a trivial £2 billion a year or so and prevented the UK from being the lowest-taxed major economy in Europe.

Getting rid of it might even raise more money. Clearly abolishing it in the middle of a cost-of-living crisis is too difficult politically. It is, however, still the right thing to do. So here’s what Truss – who has spent all her political capital on a botched attempt to scrap the tax – should do instead.

The PM should start by steadily raising the threshold so that it impacts far fewer people. If she’s feeling brave, she should take it all the way up to £500,000. In the United States, for example, the top rate of 37 per cent kicks in at $539,000 (£480,000) – and hardly anyone apart from a few fanatics on Twitter have much to say about that.

Next, Truss should add in various exemptions and allowances that could only be set against the top rate. Mortgage relief, for example, or travel expenses for work.

Finally, she should dramatically increase the thresholds for the 40 per cent rate as well. Given that £50,000 a year is a ridiculous level for people to start paying almost half their income in tax, Truss could push that all the way up to £150,000 a year, and then eventually to £200,000. And then once that had been achieved, the PM could merge the two top rates, and sell the whole package as an increase for the rich. Add up all those changes, and it would no longer exist.

Some of the biggest changes in political direction are best done under cover. Margaret Thatcher and Gordon Brown achieved some of their most significant policy changes by stealth: Thatcher did so with her slow and gradual reduction of trade union power; Brown with a steady expansion of the tax and welfare system that turned the UK into a country addicted to state support.

The Truss government – if it is not already too late for it to make any meaningful reforms – should learn to follow them. The 45 per cent rate should go: but it can only be done if nobody notices.

For a full list of Spectator Tory conference fringe events, click here