AP Photo

When Francis Maude was a junior minister at the Department of Trade and Industry, he sent a note to Margaret Thatcher detailing a particularly fiendish political problem he was struggling with, in the hope that she might offer a solution. By return, he received a one-line reply from her adviser Charles Powell, which read: "The Prime Minister has studied your note with interest and agrees it is a difficult issue." Translation: he was on his own.

In the era of the compulsive micro-manager who currently occupies Number 10, it is worth remembering that ministers were once expected (sometimes, at least) to sort things out for themselves. Lady Thatcher, whose first months in office are being studied carefully by David Cameron, has things to teach even the lowliest frontbencher about...