Who are the Trotskyites now?

It seems a long time (more than a quarter of a century, actually) since the Trots were regularly being denounced  and it is something of a political wonder that they have survived into the 21st century.
But when the Tories' backs are to the wall, you can rely on them to haul out the invective against these ultra-left demons.
David Cameron was at it today at PMQs. Asked about the government's workfare scheme, he lashed out at "the Trotskyites" (sic) who, he said, are organising the opposition to it.
It makes a change to have a new target after the beating the bankers have taken. To paraphrase Peter Mandelson: "They have suffered enough."
So who are these Trotskyites attacked so robustly by the prime minister?  Well, they are the people who run Boots. And McDonalds. And Tesco. And dozens of other major retail companies.
I thought they were capitalists but it turns out they are Trots. Presumably Cameron thinks proper business leaders could see that the workfare scheme is a wonderful opportunity for young people to work for nothing in menial jobs with the threat of losing their meagre benefits if they should dare to prefer not to be exploited.
In fact, these companies have been rather swift to respond once they realised what was going on and that they, in turn, were being exploited by the government in an attempt to make a sordid scheme look good and successful.
Can't David Cameron tell the difference between the people who run some of the biggest companies in the country and the rag-tag of the SWP? Apparently not.
Stand by for him to accuse doctors and nurses of being "Trotskyites" for opposing his health bill.