… is from page 33 of Sir Louis Mallet’s 1867 Cobden’s Work and Opinions:
When we add to these considerations the singular inaptitude of the governing classes of this country to comprehend foreign affairs, the extraordinary errors which are usually to be observed in their judgements and opinions on foreign questions, and the dangerous liability to abuse in the hands of any government, of the doctrine of “Blood and Iron,” even if it be sometimes invoked in a just cause, we shall, we think (without assenting that it must be inflexibly enforced), acknowledge the sober wisdom of [Richard] Cobden’s opinion, that, for all practical purposes, at least for this generation, the principle of non-intervention should be made, as far as general principles can be applied to such questions, the rule of our foreign policy.
I add only that what Mallet correctly understood to be true of the governing classes of mid-19th-century Great Britain is true of all governing classes of all times and in all countries.