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.

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.

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.

A British imperium enabled Scots to feel themselves peers of the Ebglish in a way still denied them in an island kingdom. The language bears that out very clearly. The English and the foreign are still all too inclined to refer to the island of Great Britain as 'England'. But at no time have they ever customarily referred to an English empire.

At one level Great Britain at the beginning of the 18th century was like the Christian doctrine of the Trinity, both three and one, and altogether something of a mystery.

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.

The pre-war empire had been sufficiently informal and sufficiently cheap for Parliament to claim authority over it without having to concern itself too much about what this authority entailed. The post-war empire necessitated a much greater investment in administrative machinery and military force. This build-up of control had to be paid for, either by British taxpayers or by their colonists.