Britain: Terror on a Summer's Day

In a grim week, the I.R.A. strikes in cold blood and new scandals erupt

The bright morning sun sparkled off the plumed metal helmets of the Blues and Royals troopers of the Queen's Household Cavalry as they left their barracks for the daily mounting of the guard at Whitehall. Resplendent in blue tunics, white buckskin breeches and silver-colored breastplates, the tips of their unsheathed swords jauntily resting on their right shoulders, the colorful 16-man troop trotted along Hyde Park's South Carriage Drive while admiring tourists lolled in the grass and snapped pictures. The cavalrymen never reached their destination. At 10:43, just...