Britain joined in the bombing of Syria last weekend, explained Theresa May, because chemical weapons must not be “normalised”. But in these abnormal times, what does that really mean?

From the mid-19th century, “normalise” has meant “to make normal” (OED) or to standardise, applied to everything from biological functions to spelling. But in modern political terms it carries the extra moral nuance of “to accept as normal”. Thus did some Democrats, after Trump’s election, call for journalists to resist “normalising” the president by writing about him as though he were a rational politician. (Since “normal” comes from the Latin for “right-angled”, perhaps they meant Trump was obtuse.) Similarly, May meant that we should not tolerate the employment of chemical weapons.

Like everything else in the world, our own bombs are also made of chemicals, and they blow human beings up, but they are defined as “conventional” weapons and therefore unobjectionable. Only the worst kind of cynic, indeed, would suggest that the only weapons allowed to be “normalised” are those we sell to other countries.