Super Tuesday: No knockout win for Romney

The Republican presidential race continues to be a hard-fought battle. We look at the social issues which have risen to the fore, as the hopefuls try to woo the right wing. Next, our reporters take us down the "narco tunnels" criss-crossing the ground under the US-Mexico border. Finally, an American author has taken the child-rearing tips she learned in France across the Atlantic, trying to sell the Gallic approach to her fellow Americans.