If we look at the entire period after the 1832 Reform Act, the Tories and their allies have carried a majority of Scottish seats only twice: in 1900 and in 1955.
As the Conservative base in Scotland dwindled, the party necessarily began to look and sound more English.
During the 1980s, many Scots noticed that, although they kept voting for one set of politicians, they were being governed by a different set. Understandably, support for devolution rose.
The Conservatives then made a huge strategic blunder, believing they could smother separatism with subsidies. Successive Scottish secretaries fought for larger and larger budgets.
But the effect of greater state spending in Scotland was to make a higher percentage of the electorate financially dependent on the government and therefore likelier to vote for the parties that favoured high taxes.
Which is why it is so strange that there are Conservatives who oppose Scottish fiscal autonomy.
When I look around the European Parliament, I notice that, in almost every other country, the centre-right parties benefit electorally from positioning themselves as the champions of local particularisms against the bureaucracy of the central state.
For a long time, the British Conservatives were the exception to the rule. One of the most significant but unremarked aspects of David Cameron's leadership is that he has reversed that alignment, embracing localism and radical decentralisation.
Conservative localism has particular implications for Scotland.
Conservatives should embrace the principle that decisions should be taken as closely as possible to the people they affect. This will mean shifting some powers from Westminster to Holyrood, but it will also mean shifting many powers from Holyrood to local councils and, indeed, shifting a few powers from the state to the citizen.
Localism would have a happy side-effect: it would solve the West Lothian Question. There is no power that was devolved to Edinburgh under the 1998 Scotland Act that could not, in England, be exercised by county or metropolitan authorities.
One more point. The best way for Scottish Conservatives to demonstrate beyond doubt that they are rooted in the local soil is to open up the selection of their parliamentary candidates to the widest possible electorate.
The UK coalition agreement provides for state-funded open primaries to be held in 200 constituencies, but there is no need to wait for the government to run such a contest.
Individual Conservative associations could simply decide to allow all residents a say in who should be their Tory candidate.
The Conservatives, in other words, should support decentralisation within their own party structures as well as within those of the United Kingdom.
Unionism is more than compatible with a belief in the maximum devolution of power. The relationship between England and Scotland, at its best, is like that between Johnson and Boswell: sometimes teasing, occasionally grumpy, but rooted in a deep affection between two free-thinking individuals.
Localism would remove the anomalies of the 1998 settlement, making the UK as a whole wealthier, more democratic and freer.
Daniel Hannan is a Conservative MEP for the South East of England and co-chairman of Direct Democracy (www.directdemocracyuk.com)