As we passed through the windows I became aware of a crowd of photographers facing the building. Glancing to my left, I saw gliding through the next set of windows the glacially poised, queenly figure of Jackie Kennedy – an impressive early lesson in how a celebrity faces her public.

The Black Watch did their stuff on the South Lawn with the expected gusto and precision. My clearest sight of the President came at the conclusion of the tattoo, when the regiment’s colonel presented him with a sgian dubh, the dagger that Highlanders carry in their socks.

A few days later, JFK was dead and Lyndon Johnson was president. LBJ had been a congressman and senator in Washington for more than 30 years before becoming Kennedy’s vice-president. He had continued to live in his Washington house as vice-president – after all, the Kennedy gang didn’t want him around – and in the first week or so of his own presidency he did not even move his toothbrush into the White House, presumably out of consideration for Jackie’s feelings.

As it happened, LBJ’s house was near ours, in the DC suburb of Spring Valley, but a few blocks further out towards the Maryland line. During those fraught days between the assassination and the state funeral, a presidential convoy used to roar down Upton Street towards Massachusetts Avenue at about 8 o’clock each morning. This was the time that we children would leave the house for the walk to the school bus stop, and we were strictly enjoined not to wave baseball bats, throw balls or otherwise make gestures that might be construed as threatening.