In the past, the British had signally failed to build an effective structure of royal authority and administration in their American colonies. As a result, no possibility existed of soothing and winning over influential and talented Americans, in the way that influential and talented Scotsmen were increasingly being won over, by giving them increased access to state employment.

Jacobitism involved much more than a debate about the merits of a particular dynasty. Men and women were well aware that its success was almost certain to involved them in civil war. And the more politically educated knew that the Stuart Pretender was a pawn in a worldwide struggle for commercial and imperial primacy between Britain and France.

In virtually every Continental state at this time, aristocracies had to live with the risk that their property might be pillaged or confiscated. Only in Great Britain did it prove possible to float the idea that aristocratic property was in some magical and strictly intangible way the people's property also. The fact that hundreds of thousands of men and women today are willing to accept that privately owned country houses and their contents are part of Britain's national heritage is one more proof of how successfully the British elite reconstructed its cultural image in an age of revolution.

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.

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.

Recognising that an ostentatious cult of heroism and state service served an important propaganda function for the British elite does not mean, of course, that we should dismiss it as artificial or insincere. All aristocracies have a strong military tradition, and for many British patricians the protracted warfare of the period was a godsend. It gave them a job, and, more important, a purpose, an opportunity to carry out what they had been trained to do since childhood: ride horses, fire guns, exercise their undoubted physical courage and tell other people what to do.

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.