The phrase 'Re-alignment of the Left' began with Jo Grimond in 1956. It happened briefly when the SDP split away from the Labour Party in 1981, but the Left then contrived to align itself back into its old dysfunctional shape.
For some reason, you almost never hear the phrase 'Re-alignment of the Right'. Yet, listening to David Cameron's speech yesterday, with the ghost of Ukip peering over his shoulder, convinced me that that may be what is happening.
The Conservative Party is an uneasy alliance between two elements which have little in common - the old-fashioned conservatism of family and community, and the new conservatism of markets and big business. Sometimes a broad Cameronian rhetoric of moderation can hold the two sides together; sometimes it can't.
The last time they came apart spectacularly was during the early years of the last century - half of them backing protectionism and 'imperial preference' and the other half a kind of liberal commitment to trade, with a rump around prime minister Balfour where they had, as one of them put it, "nailed my colours firmly to the fence".
The Ukip insurgency seems to be uniting one kind of conservatism - suspicious of foreigners - from across the parties, against the other kind. Business lobby groups are in despair. Something is about to shift.
So when former Cambridge MP David Howarth argued in the latest Liberator (not online) that there is no constituency for Jeremy Browne's vision of a new kind of free market Liberalism, there is a 'yes, but...'
Because the long-term prospect is to re-align the Right so that the old curmudgeons in Ukip take over the rump of the old Conservative Party, and the modernisers, moderates, small enterprisers and open traders join the Lib Dems.
There is a 'yes, but' here too. Because it provides an opportunity for Liberals to claw back the original meaning of 'free trade' from the conservatives and advocates of turbo-capitalism.
Free trade as it was originally understood, developed by liberals for Liberals, was the right of free people to trade with each other, communicate with each other and be hospitable to each other. It emerged out of the anti-slavery movement as the antidote to the kind of economic bondage which faced former slaves in the Deep South or former serfs in Russia.
It was not what it has become: an assertion of the right of the powerful to ride roughshod over the powerless.
It was originally an antidote for monopoly; it has become a justification of it. In the Re-alignment of the Right, if Liberals embrace it - and make the intellectual running - that has to change.
It is a historic opportunity for Liberalism to take back control of a concept which they invented. I'm rather looking forward to it, especially if we can re-align the Left at the same time.
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