President Vladimir Putin is not renowned for sentimentality. Yet for a fleeting moment half-way through his annual state of the nation address this week he became almost dewy-eyed.

"And now for the most important thing. What is the most important thing?" he asked his Kremlin audience. "Love," came a cry, somewhat improbably, from Russia's defence minister. Quite right, said the president. "I want to talk about love, women, children," he said. "And about Russia's most acute problem today - the demographic problem."