Of all the liberal dogmas to emerge out of the United Kingdom in the 19th century,
Radicalism seems to me to have been simultaneously the most intellectually profound and the most ignored. Most of what Americans today mistakenly call 'classical liberalism', in the context of discussions on social policy and
laissez-faire doctrines which are intended to be egalitarian in practice, actually originate out of this long-lost tradition, with liberalism itself being much more moderate in practice, content to concern itself with issues of protection.
The natural response is to say "they got their suffrage and their secret ballot and had no more reason to exist". But this argument doesn't get at the root of my question, which is: why did Radicalism and liberalism divorce so quickly? Liberalism took a conservative turn nearly as soon as the Corn Laws were repealed, and had begun to do so as early as the organization of the Derby Dilly. I find it odd that it should have abandoned its youthful energy so suddenly.