Contrary to received wisdom, the British are not an insular people in the conventional sense - far from it. For most of their early modern and modern history, they have had more contact with more parts of the world than almost any other nation - it is just that this contact has regularly taken the form of aggressive military and commercial enterprise.

In the last quarter of the 20th century, Britons have been understandably obsessed with the problem of having too little power in the world. In the third quarter of the 18th century, by contrast, their forebears were perplexed by the problem of having acquired too much power too quickly over too many people.

A fundamental reason why Britain was not torn apart by civil war after 1688 was that its inhabitants' aggression was channelled so regularly and so remorsely into war and imperial expansion abroad.

These developments - a massive transfer of land by way of inheritance and purchase, an unprecedented rise in the profitability of land and increasing intermarriage between Celtic and English dynasties - helped to consolidate a new unitary ruling class in place of the more separate and specific landed establishments that had characterised England, Scotland, Wales and Ireland in the Tudor and Stuart eras.

Loyal and substansial Catholic service on the battlefield undermined one of the most longstanding objections to emancipation: namely, that since Catholics owed religious allegiance to a foreign authority in the person of the Pope, their political and patriotic allegiance must necessarily be suspect.

Chilvalry's essential function, Maurice Keen has written, is always to hold up an idealised image of armed conflict in defiance of the harsh realities of actual warfare. By definition, chivalry also reaffirms the paramount importance of custom, hierarchy and inherited rank.

Contrary to received wisdom, the British are not an insular people in the conventional sense - far from it. For most of their early modern and modern history, they have had more contact with more parts of the world than almost any other nation - it is just that this contact has regularly taken the form of aggressive military and commercial enterprise.