Johannesburg — There's no doubting Finance Minister Pravin Gordhan means it when he promises us fiscal prudence. But still, that's a hell of a bet he took in his budget statement on Tuesday.

Remember, he said, government debt as a percentage of GDP would rise from 23% this last March to 41% by 2013. Interest alone on that debt will rise from R54bn a year now to almost R100bn in four years' time. And the solution? "We will bring the borrowing requirement down again in the years ahead, as economic growth improves," said Gordhan.

But a lot can happen "in the years ahead" that not even Gordhan can predict or prevent. While we trust that the money he plans to borrow will be put to good use, it still means our country is going to be placed in an extremely vulnerable position until the debt is wrestled down again.

Which is where Julius Malema comes in. The ANC Youth League president, recently endorsed by President Jacob Zuma as a future ANC leader, wants to nationalise the mines. If he makes that happen Gordhan is unlikely ever to see his "years ahead".

We are all (media included) obliged in SA to be careful what we say. And we do not ask that Malema be hammered by Zuma for his calls for nationalisation.

But as it is clear the young man is indeed going to be with us for a long time, a way has to be found to induct him into the secrets of economics. The main one is that money doesn't grow on trees. You have to pay your own way in the world. If you borrow too much, you end up paying so much interest there's no money for anything else.

Nationalisation, even partial, would divert money away from people who need it. Our mines make profits that pay taxes that build schools and hospitals. Much that can go wrong in the years ahead is out of our hands, but not this.

Malema is clearly a gifted politician, but his repeated talk of nationalisation is needlessly reckless. Someone really needs to have a talk with him before he does himself and the rest of us a serious injury.