This is cause for optimism. But we should not forget that ethnic minorities have always played an important role in the British armed services. Freed slaves from the Caribbean fought under Nelson at the Battle of Trafalgar. In the First World War, tens of thousands of Commonwealth troops served in Flanders. The Gurkhas of Nepal are some the most highly respected soldiers to wear the Queen's uniform.
Perhaps the surprising aspect of this tale is not that someone from an ethnic minority has risen to the top - but that it took so long.